id
stringlengths 9
16
| submitter
stringlengths 1
64
⌀ | authors
stringlengths 3
36.7k
| title
stringlengths 1
382
| comments
stringlengths 1
1.15k
⌀ | journal-ref
stringlengths 1
557
⌀ | doi
stringlengths 7
153
⌀ | report-no
stringlengths 1
479
⌀ | categories
stringlengths 5
125
| license
stringclasses 9
values | abstract
stringlengths 6
6.09k
| versions
list | update_date
timestamp[s] | authors_parsed
sequence |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
quant-ph/9910010 | H. J. Kimble | Samuel L. Braunstein and H. J. Kimble | Dense Coding for Continuous Variables | 4 pages, two figures, submitted to PRA | null | 10.1103/PhysRevA.61.042302 | null | quant-ph | null | A scheme to achieve dense quantum coding for the quadrature amplitudes of the
electromagnetic field is presented. The protocol utilizes shared entanglement
provided by nondegenerate parametric down conversion in the limit of large gain
to attain high efficiency. For a constraint in the mean number of photons n
associated with modulation in the signal channel, the channel capacity for
dense coding is found to be ln(1+n+n^2), which always beats coherent-state
communication and surpasses squeezed-state communication for n>1. For n>>1, the
dense coding capacity approaches twice that of either scheme.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 01:53:26 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Braunstein",
"Samuel L.",
""
],
[
"Kimble",
"H. J.",
""
]
] |
quant-ph/9910011 | null | Pavel Bona (Dept. Theor. Phys., Comenius University, Bratislava) | Geometric Formulation of Nonlinear Quantum Mechanics for Density
Matrices | Latex, 10 pages, to be published in proceedings | Proceedings of the International Symposium: Trends in Quantum
Mechanics, Goslar 1998. Eds: H.-D.Doebner, S.T.Ali, M.Keyl and R.F.Werner;
World Scientific, Singapore-New Jersey-London-Hong Kong, 2000 | null | null | quant-ph | null | Proposals for nonlinear extenstions of quantum mechanics are discussed. Two
different concepts of "mixed state" for any nonlinear version of quantum theory
are introduced: (i) >genuine mixture< corresponds to operational "mixing" of
different ensembles, and (ii) a mixture described by single density matrix
without having a canonical operational possibility to pick out its specific
convex decomposition is called here an >elementary mixture<. Time evolution of
a class of nonlinear extensions of quantum mechanics is introduced. Evolution
of an elementary mixture cannot be generally given by evolutions of components
of its arbitrary convex decompositions. The theory is formulated in a
"geometric form": It can be considered as a version of Hamiltonian mechanics on
infinite dimensional space of density matrices. A quantum interpretation of the
theory is sketched.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 14:27:34 GMT"
}
] | 2012-12-07T00:00:00 | [
[
"Bona",
"Pavel",
"",
"Dept. Theor. Phys., Comenius University, Bratislava"
]
] |
quant-ph/9910012 | null | Pavel Bona (Comenius University, Bratislava) | On Symmetries in Nonlinear Quantum Mechanics | Latex, 5 pages, submitted to Proceedings of a conference | Proceedings of the International Symposium: Quantum Theory and
Symmetries, Goslar 1999. Eds: H.-D.Doebner, V.K.Dobrev, J.-D.Hennig and
W.Luecke; World Scientific, Singapore-New Jersey-London-Hong Kong, 2000 | null | null | quant-ph | null | It is shown how nonlinear versions of quantum mechanics can be refolmulated
in terms of a (linear) C*-algebraic theory. Then also their symmetries are
described as automorphisms of the correspondong C*-algebra. The requirement of
"conservation of transition probabilities" is discussed.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 14:27:28 GMT"
}
] | 2012-12-11T00:00:00 | [
[
"Bona",
"Pavel",
"",
"Comenius University, Bratislava"
]
] |
quant-ph/9910013 | Anatoly Zhiliba | V. N. Gorbachev and A. I. Zhiliba | Transfer formalism for quantum optics problems | LaTeX file, \documentstyle[11pt,fleqn]{article} | null | 10.1088/0305-4470/33/20/304 | null | quant-ph | null | Consistent quantum formalism based on the localized basis of the Wannirer
functions in Heisenberg and Schrodinger pictures to describe propagation of
electromagnetic field in a three dimensional media including diffraction is
presented. In the Schrodinger picture the Fokker-Planck equation for the
Glauber-Sudarshan quasiprobability and corresponding Langevin equations are
given. As result the space-time description is obtained by a simple changing
variables in the temporal master equation of the field. Using this formalism it
is shown that the existence of integrals of motion in the propagation of light
in a medium under the condition of nondegenerated parametric and two-photon
interactions results in amplification of modes when nonclassical properties of
the light are conserved. Quantum propagation of light in a linear medium taking
into account the diffraction is considered and its solution is found.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 10:36:27 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Gorbachev",
"V. N.",
""
],
[
"Zhiliba",
"A. I.",
""
]
] |
quant-ph/9910014 | Hongchen Fu | Yongzheng Zhang, Hongchen Fu and Allan I. Solomon | Intermediate coherent-phase(PB) states of radiation fields and their
nonclassical properties | 9 pages, 3 EPS figures, use epsf.sty. Accepted for publication in
Phys.Lett.A | Phys.Lett.A263:257-262,1999 | 10.1016/S0375-9601(99)00705-7 | null | quant-ph | null | Intermediate states interpolating coherent states and Pegg-Barnett phase
states are investigated using the ladder operator approach. These states reduce
to coherent and Pegg-Barnett phase states in two different limits. Statistical
and squeezing properties are studied in detail.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 13:52:41 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Zhang",
"Yongzheng",
""
],
[
"Fu",
"Hongchen",
""
],
[
"Solomon",
"Allan I.",
""
]
] |
quant-ph/9910015 | Jaehyun Kim | Jaehyun Kim, Jae-Seung Lee, Soonchil Lee, and Chaejoon Cheong | Implementation of the refined Deutsch-Jozsa algorithn on a 3-bit NMR
quantum computer | 5 pages, 2 figures, 1 tables, REVTeX | Phys. Rev. A 62, 022312 (2000). | 10.1103/PhysRevA.62.022312 | null | quant-ph | null | We implemented the refined Deutsch-Jozsa algorithm on a 3-bit nuclear
magnetic resonance quantum computer, which is the meaningful test of quantum
parallelism because qubits are entangled. All of the balanced and constant
functions were realized exactly. The results agree well with theoretical
predictions and clearly distinguish the balanced functions from constant
functions. Efficient refocusing schemes were proposed for the soft z-pulse and
J-coupling and it is proved that the thermal equilibrium state gives the same
results as the pure state for this algorithm.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 14:31:02 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Kim",
"Jaehyun",
""
],
[
"Lee",
"Jae-Seung",
""
],
[
"Lee",
"Soonchil",
""
],
[
"Cheong",
"Chaejoon",
""
]
] |
quant-ph/9910016 | Paolo Zanardi | Paolo Zanardi (1,2) ((1) Istituto Nazionale per la Fisica della
Materia (INFM), (2) Institute for Scientific Interchange (ISI) Foundation) | Stabilizing Quantum Information | 5 Pages, Latex. Presentation improved, results unchanged. To appear
in PRA | Phys. Rev. A 63 (2001) 12301 | 10.1103/PhysRevA.63.012301 | null | quant-ph | null | The dynamical-algebraic structure underlying all the schemes for quantum
information stabilization is argued to be fully contained in the reducibility
of the operator algebra describing the interaction with the environment of the
coding quantum system. This property amounts to the existence of a non-trivial
group of symmetries for the global dynamics. We provide a unified framework
which allows us to build systematically new classes of error correcting codes
and noiseless subsystems. It is shown how by using symmetrization strategies
one can artificially produce noiseless subsystems supporting universal quantum
computation.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 17:45:27 GMT"
},
{
"version": "v2",
"created": "Wed, 6 Sep 2000 17:50:56 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Zanardi",
"Paolo",
""
]
] |
quant-ph/9910017 | Oscar Rosas-Ortiz | J.I. Diaz, J. Negro, L.M. Nieto and O. Rosas-Ortiz | The supersymmetric modified Poschl-Teller and delta-well potentials | 20 pages, LaTeX file, 4 eps figures | J. Phys. A: Math. Gen. 32 (1999) 8447-8460 | 10.1088/0305-4470/32/48/308 | null | quant-ph | null | New supersymmetric partners of the modified Poschl-Teller and the Dirac's
delta well potentials are constructed in closed form. The resulting
one-parametric potentials are shown to be interrelated by a limiting process.
The range of values of the parameters for which these potentials are free of
singularities is exactly determined. The construction of higher order
supersymmetric partner potentials is also investigated.
| [
{
"version": "v1",
"created": "Mon, 4 Oct 1999 21:25:07 GMT"
}
] | 2008-10-13T00:00:00 | [
[
"Diaz",
"J. I.",
""
],
[
"Negro",
"J.",
""
],
[
"Nieto",
"L. M.",
""
],
[
"Rosas-Ortiz",
"O.",
""
]
] |
quant-ph/9910018 | GuangCan Guo | Chuan-Wei Zhang, Chuan-Feng Li, and Guang-Can Guo (University of
Science and Technology of China) | No-Concentrating Theorem of Pure Entangled States | 4 Pages, no Figure, REVTeX. Minor changes in proof, result unchanged | null | null | null | quant-ph | null | Suppose two distant observers Alice and Bob share a pure biparticle entangled
state secretly chosen from a set, it is shown that Alice (Bob) can
probabilistic concentrate the state to a maximally entangled state by applying
local operations and classical communication (LQCC) if and only if the states
in the set share the same marginal density operator for her (his) subsystem.
Applying this result, we present probabilistic superdense coding and show that
perfect purification of mixed state is impossible using only LQCC on individual
particles.
| [
{
"version": "v1",
"created": "Tue, 5 Oct 1999 09:07:54 GMT"
},
{
"version": "v2",
"created": "Sat, 22 Jan 2000 08:36:27 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Zhang",
"Chuan-Wei",
"",
"University of\n Science and Technology of China"
],
[
"Li",
"Chuan-Feng",
"",
"University of\n Science and Technology of China"
],
[
"Guo",
"Guang-Can",
"",
"University of\n Science and Technology of China"
]
] |
quant-ph/9910019 | Aurelian Isar | A. Isar | Uncertainty, entropy and decoherence of the damped harmonic oscillator
in the Lindblad theory of open quantum systems | 41 pages, LaTex | Fortschritte der Physik, 47 (1999) 855-879 | 10.1002/(SICI)1521-3978(199909)47:7/8<855::AID-PROP855>3.0.CO;2-Z | null | quant-ph | null | In the framework of the Lindblad theory for open quantum systems, expressions
for the density operator, von Neumann entropy and effective temperature of the
damped harmonic oscillator are obtained. The entropy for a state characterized
by a Wigner distribution function which is Gaussian in form is found to depend
only on the variance of the distribution function. We give a series of
inequalities, relating uncertainty to von Neumann entropy and linear entropy.
We analyze the conditions for purity of states and show that for a special
choice of the diffusion coefficients, the correlated coherent states (squeezed
coherent states) are the only states which remain pure all the time during the
evolution of the considered system. These states are also the most stable under
evolution in the presence of the environment and play an important role in the
description of environment induced decoherence.
| [
{
"version": "v1",
"created": "Tue, 5 Oct 1999 10:15:12 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Isar",
"A.",
""
]
] |
quant-ph/9910020 | Slobodan Prvanovic | S. Prvanovic and Z. Maric, Belgrade, Serbia | Toward the Collapse of State | 18 pages, no figures | null | null | null | quant-ph | null | The basic concepts of classical mechanics are given in the operator form.
Then, the hybrid systems approach, with the operator formulation of both
quantum and classical sector, is applied to the case of an ideal nonselective
measurement. It is found that the dynamical equation, consisting of the
Schr\"odinger and Liouville dynamics, produces noncausal evolution when the
initial state of measured system and measuring apparatus is chosen to be as it
is demanded in discussions regarding the problem of measurement. Nonuniqueness
of possible realizations of transition from pure noncorrelated to mixed
correlated state is analyzed in details. It is concluded that collapse of state
is the only possible way of evolution of physical systems in this case.
| [
{
"version": "v1",
"created": "Tue, 5 Oct 1999 13:09:36 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Prvanovic",
"S.",
""
],
[
"Maric",
"Z.",
""
],
[
"Belgrade",
"",
""
],
[
"Serbia",
"",
""
]
] |
quant-ph/9910021 | GuangCan Guo | Wan-Li Li, Chuan-Feng Li and Guang-Can Guo (University of Science and
Technology of China) | Probabilistic teleportation and entanglement matching | 3.5 pages, No figures | Phys. Rev. A 61, 034301 (2000) | 10.1103/PhysRevA.61.034301 | null | quant-ph | null | Teleportation may be taken as sending and extracting quantum information
through quantum channels. In this report, it is shown that to get the maximal
probability of exact teleportation through partially entangled quantum
channels, the sender (Alice) need only to operate a measurement which satisfy
an ``entanglement matching'' to this channel. An optimal strategy is also
provided for the receiver (Bob) to extract the quantum information by adopting
general evolutions.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 03:51:19 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Li",
"Wan-Li",
"",
"University of Science and\n Technology of China"
],
[
"Li",
"Chuan-Feng",
"",
"University of Science and\n Technology of China"
],
[
"Guo",
"Guang-Can",
"",
"University of Science and\n Technology of China"
]
] |
quant-ph/9910022 | Duer Wolfgang | W. D\"ur, J. I. Cirac, M. Lewenstein and D. Bruss | Distillability and partial transposition in bipartite systems | 8 pages, 1 figure | Phys. Rev. A 61, 062313 (2000) | 10.1103/PhysRevA.61.062313 | null | quant-ph | null | We study the distillability of a certain class of bipartite density operators
which can be obtained via depolarization starting from an arbitrary one. Our
results suggest that non-positivity of the partial transpose of a density
operator is not a sufficient condition for distillability, when the dimension
of both subsystems is higher than two.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 07:17:00 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Dür",
"W.",
""
],
[
"Cirac",
"J. I.",
""
],
[
"Lewenstein",
"M.",
""
],
[
"Bruss",
"D.",
""
]
] |
quant-ph/9910023 | Dr. V. Krasnoholovets | Volodymyr Krasnoholovets and Dmytro Ivanovsky | Motion of a particle and the vacuum | 18 pages, LaTeX 2e, 5 figures (PostScript files) | Physics Essays, vol. 6, no. 4, pp. 554-563 (1993) | null | null | quant-ph | null | We propose the deterministic dynamics of a free particle in a physical
vacuum, which is considered as a discrete (quantum) medium. The motion of the
particle is studied taking into account its interactions with the medium. It is
assumed that this interaction results in the appearance of special virtual
excitations, called "inertons," in the vacuum medium in the surroundings of the
canonical particle. The solution of the equation of motion shows that a cloud
of inertons oscillates around the particle with amplitude $\Lambda=\lambda
v/c$, where $\lambda$ is the de Broglie wavelength, v is the initial velocity
of the particle, and c is the initial velocity of the inertons (velocity of
light). This oscillating nature of motion is also applied to the particle, and
the de Broglie wavelength $\lambda$ becomes the amplitude of spacial
oscillations. The oscillation frequency $\nu$ is given by the relation
$E=h\nu$. The connection of the present model with orthodox nonrelativistic
wave mechanics is analyzed.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 11:30:47 GMT"
},
{
"version": "v2",
"created": "Fri, 5 Nov 1999 08:34:47 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Krasnoholovets",
"Volodymyr",
""
],
[
"Ivanovsky",
"Dmytro",
""
]
] |
quant-ph/9910024 | Benjamin Varcoe | B.T.H. Varcoe, R. Sang, W.R. MacGillivray, and M.C. Standage | Quantum State Reconstruction Using Atom Optics | 4 pages, 4 figures | null | null | null | quant-ph | null | We present a novel technique in which the total internal quantum state of an
atom may be reconstructed via the measurement of the momentum transferred to an
atom following its interaction with a near resonant travelling wave laser beam.
We present the first such measurement and demonstrate the feasibility of the
technique.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 13:51:17 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Varcoe",
"B. T. H.",
""
],
[
"Sang",
"R.",
""
],
[
"MacGillivray",
"W. R.",
""
],
[
"Standage",
"M. C.",
""
]
] |
quant-ph/9910025 | Kentaro Imafuku | Kentaro Imafuku, Kazuya Yuasa and Ichiro Ohba (Waseda University,
Tokyo, Japan) | Quantum stochastic resonance in driven spin-boson system with stochastic
limit approximation | 9 pages with 6 figures | null | null | WU-HEP-99-9 | quant-ph | null | After a brief review of stochastic limit approximation with spin-boson system
from physical points of view, amplification phenomenon-stochastic resonance
phenomenon-in driven spin-boson system is observed which is helped by the
quantum white noise introduced through the stochastic limit approximation. The
shift in frequency of the system due to the interaction with the
environment-Lamb shift-has an important role in these phenomena.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 14:33:00 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Imafuku",
"Kentaro",
"",
"Waseda University,\n Tokyo, Japan"
],
[
"Yuasa",
"Kazuya",
"",
"Waseda University,\n Tokyo, Japan"
],
[
"Ohba",
"Ichiro",
"",
"Waseda University,\n Tokyo, Japan"
]
] |
quant-ph/9910026 | David DiVincenzo | David P. DiVincenzo (IBM), Peter W. Shor (AT&T), John A. Smolin (IBM),
Barbara M. Terhal (IBM), Ashish V. Thapliyal (UCSB) | Evidence for Bound Entangled States with Negative Partial Transpose | Revtex, 19 pages, 2 eps figures. v2,3: very minor changes, submitted
to Phys. Rev. A. v4: minor typos corrected | Phys. Rev. A 61, 062312 (2000) | 10.1103/PhysRevA.61.062312 | null | quant-ph | null | We exhibit a two-parameter family of bipartite mixed states $\rho_{bc}$, in a
$d\otimes d$ Hilbert space, which are negative under partial transposition
(NPT), but for which we conjecture that no maximally entangled pure states in
$2\otimes 2$ can be distilled by local quantum operations and classical
communication (LQ+CC). Evidence for this undistillability is provided by the
result that, for certain states in this family, we cannot extract entanglement
from any arbitrarily large number of copies of $\rho_{bc}$ using a projection
on $2\otimes 2$. These states are canonical NPT states in the sense that any
bipartite mixed state in any dimension with NPT can be reduced by LQ+CC
operations to an NPT state of the $\rho_{bc}$ form. We show that the main
question about the distillability of mixed states can be formulated as an open
mathematical question about the properties of composed positive linear maps.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 15:18:09 GMT"
},
{
"version": "v2",
"created": "Thu, 7 Oct 1999 19:57:09 GMT"
},
{
"version": "v3",
"created": "Fri, 27 Oct 2000 18:56:45 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"DiVincenzo",
"David P.",
"",
"IBM"
],
[
"Shor",
"Peter W.",
"",
"AT&T"
],
[
"Smolin",
"John A.",
"",
"IBM"
],
[
"Terhal",
"Barbara M.",
"",
"IBM"
],
[
"Thapliyal",
"Ashish V.",
"",
"UCSB"
]
] |
quant-ph/9910027 | Diego A. R. Dalvit | Diego A. R. Dalvit and Paulo A. Maia Neto | Decoherence via Dynamical Casimir Effect | 4 pages, 2 figures | Phys.Rev.Lett.84:798-801,2000 | 10.1103/PhysRevLett.84.798 | null | quant-ph hep-th | null | We derive a master equation for a mirror interacting with the vacuum field
via radiation pressure. The dynamical Casimir effect leads to decoherence of a
'Schroedinger cat' state in a time scale that depends on the degree of
'macroscopicity' of the state components, and which may be much shorter than
the relaxation time scale. Coherent states are selected by the interaction as
pointer states.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 15:54:42 GMT"
}
] | 2011-08-04T00:00:00 | [
[
"Dalvit",
"Diego A. R.",
""
],
[
"Neto",
"Paulo A. Maia",
""
]
] |
quant-ph/9910028 | Leah Henderson | L. Henderson, L. Hardy and V. Vedral | Two-state teleportation | 20 pages, 6 figures | null | 10.1103/PhysRevA.61.062306 | null | quant-ph | null | Quantum teleportation with additional a priori information about the input
state achieves higher fidelity than teleportation of a completely unknown
state. However, perfect teleportation of two non-orthogonal input states
requires the same amount of entanglement as perfect teleportation of an unknown
state, namely one ebit. We analyse how well two-state teleportation can be
achieved using every degree of pure-state entanglement, and discuss the
fidelity of `teleportation' that can be achieved with only classical
communication but no shared entanglement. A two-state telecloning scheme is
constructed.
| [
{
"version": "v1",
"created": "Wed, 6 Oct 1999 17:08:45 GMT"
},
{
"version": "v2",
"created": "Wed, 23 Feb 2000 11:35:00 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Henderson",
"L.",
""
],
[
"Hardy",
"L.",
""
],
[
"Vedral",
"V.",
""
]
] |
quant-ph/9910029 | Jens Clausen | J. Clausen, M. Dakna, L. Knoll, D.-G. Welsch | Measuring quantum state overlaps of traveling optical fields | 17 pages, 6 figures, using a4.sty | Opt. Commun. 179, 189 (2000) | 10.1016/S0030-4018(99)00537-4 | null | quant-ph | null | We propose a detection scheme for measuring the overlap of the quantum state
of a weakly excited traveling-field mode with a desired reference quantum
state, by successive mixing the signal mode with modes prepared in coherent
states and performing photon-number measurements in an array of beam splitters.
To illustrate the scheme, we discuss the measurement of the quantum phase and
the detection of Schrodinger-cat-like states.
| [
{
"version": "v1",
"created": "Thu, 7 Oct 1999 14:26:02 GMT"
}
] | 2016-05-10T00:00:00 | [
[
"Clausen",
"J.",
""
],
[
"Dakna",
"M.",
""
],
[
"Knoll",
"L.",
""
],
[
"Welsch",
"D. -G.",
""
]
] |
quant-ph/9910030 | Christopher A. Fuchs | Samuel L. Braunstein, Christopher A. Fuchs, and H. J. Kimble | Criteria for Continuous-Variable Quantum Teleportation | 12 pages, to appear in Journal of Modern Optics | null | 10.1080/09500340008244041 | null | quant-ph | null | We derive an experimentally testable criterion for the teleportation of
quantum states of continuous variables. This criterion is especially relevant
to the recent experiment of Furusawa et al. [Science 282, 706-709 (1998)] where
an input-output fidelity of $0.58 \pm 0.02$ was achieved for optical coherent
states. Our derivation demonstrates that fidelities greater than 1/2 could not
have been achieved through the use of a classical channel alone; quantum
entanglement was a crucial ingredient in the experiment.
| [
{
"version": "v1",
"created": "Thu, 7 Oct 1999 17:43:06 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Braunstein",
"Samuel L.",
""
],
[
"Fuchs",
"Christopher A.",
""
],
[
"Kimble",
"H. J.",
""
]
] |
quant-ph/9910031 | Gavin Brennen | G.K. Brennen (1), I.H. Deutsch (1), P.S. Jessen (2) ((1) University of
New Mexico, (2) University of Arizona) | Entangling Dipole-Dipole Interactions and Quantum Logic in Optical
Lattices | 53 pages, 7 figures | null | 10.1103/PhysRevA.61.062309 | null | quant-ph | null | We study a means of creating multiparticle entanglement of neutral atoms
using pairwise controlled dipole-dipole interactions in a three dimensional
optical lattice. For tightly trapped atoms the dipolar interaction energy can
be much larger than the photon scattering rate, and substantial coherent
evolution of the two-atom state can be achieved before decoherence occurs.
Excitation of the dipoles can be made conditional on the atomic states,
allowing for deterministic generation of entanglement. We derive selection
rules and a figure-of-merit for the dipole-dipole interaction matrix elements,
for alkali atoms with hyperfine structure and trapped in well localized center
of mass states. Different protocols are presented for implementing two-qubits
quantum logic gates such as the controlled-phase and swap gate. We analyze the
fidelity of our gate designs, imperfect due to decoherence from cooperative
spontaneous emission and coherent couplings outside the logical basis. Outlines
for extending our model to include the full molecular interactions potentials
are discussed.
| [
{
"version": "v1",
"created": "Thu, 7 Oct 1999 20:56:32 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Brennen",
"G. K.",
""
],
[
"Deutsch",
"I. H.",
""
],
[
"Jessen",
"P. S.",
""
]
] |
quant-ph/9910032 | Supriyo Bandyopadhyay | Supriyo Bandyopadhyay | A Self Assembled Nanoelectronic Quantum Computer Based on the Rashba
Effect in Quantum Dots | 22 pages, 4 figures | Physical Review B, Vol. 61, 13813 (2000) | 10.1103/PhysRevB.61.13813 | null | quant-ph | null | Quantum computers promise vastly enhanced computational power and an uncanny
ability to solve classically intractable problems. However, few proposals exist
for robust, solid state implementation of such computers where the quantum
gates are sufficiently miniaturized to have nanometer-scale dimensions. Here I
present a new approach whereby a complete computer with nanoscale gates might
be self-assembled using chemical synthesis. Specifically, I demonstrate how to
self-assemble the fundamental unit of this quantum computer - a 2-qubit
universal quantum controlled-NOT gate - based on two exchange coupled
multilayered quantum dots. Then I show how these gates can be wired using
thiolated conjugated molecules as electrical connectors. A qubit is encoded in
the ground state of a quantum dot spin-split by the Rashba interaction.
Arbitrary qubit rotations are effected by bringing the spin splitting energy in
a target quantum dot in resonance with a global ac magnetic field by applying a
potential pulse of appropriate amplitude and duration to the dot. The
controlled dynamics of the 2-qubit controlled-NOT operation (XOR) can be
realized by exploiting the exchange coupling with the nearest neighboring dot.
A complete prescription for initialization of the computer and data
input/output operations is presented.
| [
{
"version": "v1",
"created": "Thu, 7 Oct 1999 22:50:15 GMT"
},
{
"version": "v2",
"created": "Thu, 7 Oct 1999 23:18:40 GMT"
},
{
"version": "v3",
"created": "Mon, 29 Nov 1999 21:27:52 GMT"
},
{
"version": "v4",
"created": "Mon, 27 Mar 2000 01:00:07 GMT"
},
{
"version": "v5",
"created": "Sun, 9 Apr 2000 22:38:00 GMT"
},
{
"version": "v6",
"created": "Tue, 7 Nov 2000 22:58:54 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Bandyopadhyay",
"Supriyo",
""
]
] |
quant-ph/9910033 | Lane A. Hemaspaandra | Edith Hemaspaandra (RIT), Lane A. Hemaspaandra (University of
Rochester), Marius Zimand (Towson University) | Almost-Everywhere Superiority for Quantum Computing | 16 pages | null | null | Revised version of URCS-TR-99-720 | quant-ph cs.CC | null | Simon as extended by Brassard and H{\o}yer shows that there are tasks on
which polynomial-time quantum machines are exponentially faster than each
classical machine infinitely often. The present paper shows that there are
tasks on which polynomial-time quantum machines are exponentially faster than
each classical machine almost everywhere.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 03:48:56 GMT"
},
{
"version": "v2",
"created": "Mon, 11 Oct 1999 19:03:38 GMT"
},
{
"version": "v3",
"created": "Wed, 20 Oct 1999 22:33:57 GMT"
},
{
"version": "v4",
"created": "Sat, 29 Apr 2000 23:40:58 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Hemaspaandra",
"Edith",
"",
"RIT"
],
[
"Hemaspaandra",
"Lane A.",
"",
"University of\n Rochester"
],
[
"Zimand",
"Marius",
"",
"Towson University"
]
] |
quant-ph/9910034 | Molotkov S. | S.N.Molotkov and S.S.Nazin (Institute of Solid State Physics, Russian
Academy of Sciences) | Relativistic quantum coin tossing | 6 pages, no figures | null | 10.1134/1.568249 | null | quant-ph | null | A relativistic quantum information exchange protocol is proposed allowing two
distant users to realize ``coin tossing'' procedure. The protocol is based on
the point that in relativistic quantum theory reliable distinguishing between
the two orthogonal states generally requires a finite time depending on the
structure of these states.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 09:32:49 GMT"
},
{
"version": "v2",
"created": "Fri, 22 Oct 1999 09:24:03 GMT"
},
{
"version": "v3",
"created": "Mon, 25 Oct 1999 08:32:21 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Molotkov",
"S. N.",
"",
"Institute of Solid State Physics, Russian\n Academy of Sciences"
],
[
"Nazin",
"S. S.",
"",
"Institute of Solid State Physics, Russian\n Academy of Sciences"
]
] |
quant-ph/9910035 | Pavel Exner | P.Duclos, P.Exner, and D. Krejcirik | Locally curved quantum layers | LaTeX2e, 15 pages, to appear in the Ukrainian J. Phys., Bogolyubov
Memorial Issue | Ukrainian J. Phys. 45 (2000), 595-601 | null | null | quant-ph cond-mat math-ph math.MP | null | We consider a quantum particle constrained to a curved layer of a constant
width built over an infinite smooth surface. We suppose that the latter is a
locally deformed plane and that the layer has the hard-wall boundary. Under
this assumptions we prove that the particle Hamiltonian possesses geometrically
induced bound states.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 13:03:42 GMT"
}
] | 2020-01-30T00:00:00 | [
[
"Duclos",
"P.",
""
],
[
"Exner",
"P.",
""
],
[
"Krejcirik",
"D.",
""
]
] |
quant-ph/9910036 | W. A. Hofer | W.a. Hofer | A realist view of the electron: recent advances and unsolved problems | 9 pages (RevTeX, twocolumn) with 7 figures (eps), to appear in
Contemporary Fundamental Physics, Nova Science. Related papers are found at
http://info.tuwien.ac.at/cms/wh/ | null | null | null | quant-ph hep-th | null | In view of experimentally obtainable resolutions, equal to the Compton
wavelength of an electron, the conventional interpretation of quantum mechanics
no longer seems to provide a sufficiently subtle tool. Based on the intrinsic
properties of extended particles we propose a new theory, which allows to
describe fundamental processes with unlimited precision at the microlevel. It
is shown how this framework combines classical electrodynamics and quantum
mechanics in a single and consistent picture. An analysis of single measurement
problems reveals that the theory is suitable to remove some of the most
striking paradoxes in quantum mechanics, which are found to originate from
obscuring statistical effects with physical reasoning. A possible origin of the
infinity problems in relativistic quantum fields is found by analyzing electron
accelerations due to photon absorption processes. The current state of the
theory and existing problems are discussed briefly.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 13:38:43 GMT"
}
] | 2009-09-25T00:00:00 | [
[
"Hofer",
"W. a.",
""
]
] |
quant-ph/9910037 | BG Englert | Berthold-Georg Englert, Marlan O. Scully, and Herbert Walther | On mechanisms that enforce complementarity | 4 pages | Journal of Modern Optics, vol. 47, 2000, pp. 2213-2220 | 10.1080/09500340008235143 | null | quant-ph | null | In a recent publication Luis and Sanchez-Soto arrive at the conclusion that
complementarity is universally enforced by random classical phase kicks. We
disagree. One could just as well argue that quantum entanglement is the
universal mechanism. Both claims of universality are unjustified, however.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 13:18:23 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Englert",
"Berthold-Georg",
""
],
[
"Scully",
"Marlan O.",
""
],
[
"Walther",
"Herbert",
""
]
] |
quant-ph/9910038 | Oscar Rosas-Ortiz | J. Negro, L.M. Nieto and O. Rosas-Ortiz | Refined Factorizations of Solvable Potentials | 11 pages, LaTeX file, no figures | J. Phys. A: Math. Gen. 33(2000) 7207-7216 | 10.1088/0305-4470/33/40/315 | null | quant-ph | null | A generalization of the factorization technique is shown to be a powerful
algebraic tool to discover further properties of a class of integrable systems
in Quantum Mechanics. The method is applied in the study of radial oscillator,
Morse and Coulomb potentials to obtain a wide set of raising and lowering
operators, and to show clearly the connection that link these systems.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 13:46:42 GMT"
}
] | 2008-10-13T00:00:00 | [
[
"Negro",
"J.",
""
],
[
"Nieto",
"L. M.",
""
],
[
"Rosas-Ortiz",
"O.",
""
]
] |
quant-ph/9910039 | Johann Summhammer | Johann Summhammer | Maximum predictive power and the superposition principle | 6 pages, Latex, no figures | null | null | null | quant-ph | null | Recently, there has been a discussion on the origin of the quantum
probability rules (Deutsch quant-ph/9906015, Polley quant-ph/9906124, Barnum et
al. quant-ph/9907024, Finkelstein quant-ph/9907004). This contribution, which
is a slightly reformulated version of a paper published in Int.J.Theor.Phys.
33, 171 (1994), points out the follwoing: To an experimenter the world is a
persistent stream of discrete data. All that is certain is that with each
observation he/she knows more than before, simply because he/she can now answer
the question "Which of the possible outcomes have you just registered?", while
this was not possible before the observation. One can ask whether this
relentless increase of information entails a specific structure. In particular,
how must different observations be related in order to ensure that predictions
become ever more accurate, the more past observations serve as input? This
leads to the quantum rule for adding the complex square roots of probabilities,
and not to adding the probabilities themselves, as classical probability would
have it.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 13:48:22 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Summhammer",
"Johann",
""
]
] |
quant-ph/9910040 | Alberto C. de la Torre | A. C. de la Torre, A. Daleo, I. Garcia-Mata | The Photon-Box Bohr-Einstein Debate Demithologized | 10 pages, revtex, no figures | Eur. J. Phys. 21, 253-260, 2000. | null | null | quant-ph | null | The legendary discussion between Einstein and Bohr concerning the photon box
experiment is critically analyzed. It is shown that Einstein's argument is
flawed and Bohr's reply is wrong.
| [
{
"version": "v1",
"created": "Fri, 8 Oct 1999 22:44:53 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"de la Torre",
"A. C.",
""
],
[
"Daleo",
"A.",
""
],
[
"Garcia-Mata",
"I.",
""
]
] |
quant-ph/9910041 | Susana F. Huelga | J. M. G. Sancho (1) and S. F. Huelga (1,2) ((1) Departamento de
Fisica. Universidad de Oviedo. Spain. (2) Optics Section. The Blackett
Laboratory. Imperial College. London, UK) | Measuring the entanglement of bipartite pure states | 1 figure | null | 10.1103/PhysRevA.61.042303 | null | quant-ph | null | The problem of the experimental determination of the amount of entanglement
of a bipartite pure state is addressed. We show that measuring a single
observable does not suffice to determine the entanglement of a given unknown
pure state of two particles. Possible minimal local measuring strategies are
discussed and a comparison is made on the basis of their best achievable
precision.
| [
{
"version": "v1",
"created": "Sat, 9 Oct 1999 10:46:24 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Sancho",
"J. M. G.",
""
],
[
"Huelga",
"S. F.",
""
]
] |
quant-ph/9910042 | Bassano Vacchini | L. Lanz, O. Melsheimer and B. Vacchini | Description of isolated macroscopic systems inside quantum mechanics | 13 pages, latex, romp31 style, no figures, to appear in the
Proceedings of the XXXI Symposium on Mathematical Physics (Torun, Poland), to
be published in Rep. Math. Phys | Rep. Math. Phys. 46 (2000) 191-202 | 10.1016/S0034-4877(01)80023-9 | null | quant-ph | null | For an isolated macrosystem classical state parameters $\zeta(t)$ are
introduced inside a quantum mechanical treatment. By a suitable mathematical
representation of the actual preparation procedure in the time interval
$[T,t_0]$ a statistical operator is constructed as a solution of the Liouville
von Neumann equation, exhibiting at time $t$ the state parameters $\zeta(t')$,
$t_0\leq t' \leq t$, and {\it preparation parameters} related to times $T \leq
t'\leq t_0$. Relation with Zubarev's non-equilibrium statistical operator is
discussed. A mechanism for memory loss is investigated and time evolution by a
semigroup is obtained for a restricted set of relevant observables, slowly
varying on a suitable time scale.
| [
{
"version": "v1",
"created": "Sat, 9 Oct 1999 13:57:06 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Lanz",
"L.",
""
],
[
"Melsheimer",
"O.",
""
],
[
"Vacchini",
"B.",
""
]
] |
quant-ph/9910043 | Jian-Wei Pan | Dik Bouwmeester, Jian-Wei Pan, Harald Weinfurter, and Anton Zeilinger | High-Fidelity Teleportation of Independent Qubits | 13 pages, Latex, 5 figures(eps), to appear in Journal of Modern
Optics | null | 10.1080/09500340008244042 | null | quant-ph | null | Quantum teleportation is one of the essential primitives of quantum
communication. We suggest that any quantum teleportation scheme can be
characterized by its efficiency, i.e. how often it succeeds to teleport, its
fidelity, i.e. how well the input state is reproduced at the output, and by its
insensitivity to cross talk, i.e. how well it rejects an input state that is
not intended to teleport. We discuss these criteria for the two teleportation
experiments of independent qubits which have been performed thus far. In the
first experiment (Nature {\bf 390},575 (1997)) where the qubit states were
various different polarization states of photons, the fidelity of teleportation
was as high as 0.80 $\pm$ 0.05 thus clearly surpassing the limit of 2/3 which
can, in principle, be obtained by a direct measurement on the qubit and
classical communication. This high fidelity is confirmed in our second
experiment (Phys. Rev. Lett. {\bf 80}, 3891 (1998)), demonstrating entanglement
swapping, that is, realizing the teleportation of a qubit which itself is still
entangled to another one. This experiment is the only one up to date that
demonstrates the teleportation of a genuine unknown quantum state.
| [
{
"version": "v1",
"created": "Sat, 9 Oct 1999 14:08:52 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Bouwmeester",
"Dik",
""
],
[
"Pan",
"Jian-Wei",
""
],
[
"Weinfurter",
"Harald",
""
],
[
"Zeilinger",
"Anton",
""
]
] |
quant-ph/9910044 | Theor. Phys. Group | Qiong-gui Lin | Scattering of relativistic particles by a Coulomb field in two
dimensions | REVTeX, 9 pages, no figure | Phys.Lett. A260 (1999) 17-23 | 10.1016/S0375-9601(99)00507-1 | null | quant-ph hep-th | null | The scattering of relativistic Dirac particles by a Coulomb field $\pm
Ze^2/r$ in two dimensions is studied and the scattering amplitude is obtained
as a partial wave series. For small $Z$ the series can be summed up
approximately to give a closed form. The result, though being aproximate,
exhibites some nonperturbative feature and cannot be obtained from perturbative
quantum electrodynamics at the tree level.
| [
{
"version": "v1",
"created": "Mon, 11 Oct 1999 13:16:26 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Lin",
"Qiong-gui",
""
]
] |
quant-ph/9910045 | Dagomir Kaszlikowski | Marek Zukowski and Dagomir Kaszlikowski | Critical visibility for N-particle Greenberger-Horne-Zeilinger
correlations to violate local realism | 8 pages, LaTex | Phys. Rev. A 56, 1997, R1685 | null | null | quant-ph | null | A sequence of Bell inequalities for N-particle systems, which involve three
settings of each of the local measuring apparatuses, is derived. For
Greenberger-Horne-Zeilinger states, quantum mechanics violates these
inequalities by factors exponentially growing with N. The threshold
visibilities of the multiparticle sinusoidal interference fringes, for which
local realistic theories are ruled out, decrease as (2/3)^N.
| [
{
"version": "v1",
"created": "Mon, 11 Oct 1999 16:26:14 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Zukowski",
"Marek",
""
],
[
"Kaszlikowski",
"Dagomir",
""
]
] |
quant-ph/9910046 | Nipun Vats | Nipun Vats, Terry Rudolph and Sajeev John | Quantum information processing in localized modes of light within a
photonic band-gap material | RevTeX, 4 pages, 2 figures | null | null | null | quant-ph physics.atom-ph | null | The single photon occupation of a localized field mode within an engineered
network of defects in a photonic band-gap (PBG) material is proposed as a unit
of quantum information (qubit). Qubit operations are mediated by
optically-excited atoms interacting with these localized states of light as the
atoms traverse the connected void network of the PBG structure. We describe
conditions under which this system can have independent qubits with
controllable interactions and very low decoherence, as required for quantum
computation.
| [
{
"version": "v1",
"created": "Mon, 11 Oct 1999 19:49:47 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Vats",
"Nipun",
""
],
[
"Rudolph",
"Terry",
""
],
[
"John",
"Sajeev",
""
]
] |
quant-ph/9910047 | Weiqin Chao | R. Friedberg, T. D. Lee, W. Q. Zhao | Relations Between Low-lying Quantum Wave Functions and Solutions of the
Hamilton-Jacobi Equation | LaTex, 48 pages, no figure | null | 10.1007/BF03035922 | null | quant-ph | null | We discuss a new relation between the low lying Schroedinger wave function of
a particle in a one-dimentional potential V and the solution of the
corresponding Hamilton-Jacobi equation with -V as its potential. The function V
is $\geq 0$, and can have several minina (V=0). We assume the problem to be
characterized by a small anhamornicity parameter $g^{-1}$ and a much smaller
quantum tunneling parameter $\epsilon$ between these different minima.
Expanding either the wave function or its energy as a formal double power
series in $g^{-1}$ and $\epsilon$, we show how the coefficients of
$g^{-m}\epsilon^n$ in such an expansion can be expressed in terms of definite
integrals, with leading order term determined by the classical solution of the
Hamilton-Jacobi equation. A detailed analysis is given for the particular
example of quartic potential $V={1/2}g^2(x^2-a^2)^2$.
| [
{
"version": "v1",
"created": "Tue, 12 Oct 1999 03:05:50 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Friedberg",
"R.",
""
],
[
"Lee",
"T. D.",
""
],
[
"Zhao",
"W. Q.",
""
]
] |
quant-ph/9910048 | Christoph Simon | Christoph Simon, Gregor Weihs, and Anton Zeilinger (University of
Vienna) | Optimal Quantum Cloning via Stimulated Emission | 4 pages, 3 figures | Phys. Rev. Lett. 84, 2993 (2000) | 10.1103/PhysRevLett.84.2993 | null | quant-ph | null | We show that optimal universal quantum cloning can be realized via stimulated
emission. Universality of the cloning procedure is achieved by choosing systems
that have appropriate symmetries. We first discuss a scheme based on stimulated
emission in certain three-level-systems, e.g. atoms in a cavity. Then we
present a way of realizing optimal universal cloning based on stimulated
parametric down-conversion. This scheme also implements the optimal universal
NOT operation.
| [
{
"version": "v1",
"created": "Tue, 12 Oct 1999 13:41:52 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Simon",
"Christoph",
"",
"University of\n Vienna"
],
[
"Weihs",
"Gregor",
"",
"University of\n Vienna"
],
[
"Zeilinger",
"Anton",
"",
"University of\n Vienna"
]
] |
quant-ph/9910049 | Pankaj Sharan | P. Chingangbam, Pankaj Sharan (Physics Department, Jamia Millia
Islamia, New Delhi) | Reduced phase space quantization | 3 pages, REVTEX | null | null | null | quant-ph | null | We examine two singular Lagrangian systems with constraints which apparently
reduce the phase space to a 2-dimensional sphere and a 2-dimensional
hyperboloid. Rigorous constraint analysis by Dirac's method, however, gives
2-dimensional open disc and an infinite plane with a hole in the centre
respectively as the reduced phase spaces. Upon canonical quantisation the
classical constraints show up as restrictions on the Hilbert space.
| [
{
"version": "v1",
"created": "Wed, 13 Oct 1999 09:37:45 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Chingangbam",
"P.",
"",
"Physics Department, Jamia Millia\n Islamia, New Delhi"
],
[
"Sharan",
"Pankaj",
"",
"Physics Department, Jamia Millia\n Islamia, New Delhi"
]
] |
quant-ph/9910050 | Alina Suzko | A.A.Suzko (Joint Institute for Nuclear Research, Dubna, Russia) | Generalized Algebraic Bargmann - Darboux Transformations | 6 pages, Latex | International Journal of Modern Physics A, 12 (1997) 277-282 | 10.1142/S0217751X97000414 | null | quant-ph | null | Algebraic Bargmann and Darboux transformations for equations of a more
general form than the Schr\"odinger ones with an additional functional
dependence h(r) in the right-hand side of equations are constructed. The
suggested generalized transformations turn into the Bargmann and Darboux
transformations for both fixed and variable values of energy and an angular
momentum.
| [
{
"version": "v1",
"created": "Wed, 13 Oct 1999 14:00:35 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Suzko",
"A. A.",
"",
"Joint Institute for Nuclear Research, Dubna, Russia"
]
] |
quant-ph/9910051 | A. B. Balantekin | A.N.F. Aleixo (1 and 2), A.B. Balantekin (1), and M.A. Candido Ribeiro
(3) ((1) Physics Department, University of Wisconsin-Madison; (2) Instituto
de Fisica, Universidade Federal do Rio de Janeiro, (3) Departamento de Fisica
- Instituto de Biociencias, UNESP, Sao Jose do Rio Preto, SP, Brazil) | Barrier Penetration for Supersymmetric Shape-Invariant Potentials | null | J.Phys.A33:1503-1518,2000 | 10.1088/0305-4470/33/8/302 | null | quant-ph nucl-th | null | Exact reflection and transmission coefficients for supersymmetric
shape-invariant potentials barriers are calculated by an analytical
continuation of the asymptotic wave functions obtained via the introduction of
new generalized ladder operators. The general form of the wave function is
obtained by the use of the F-matrix formalism of Froman and Froman which is
related to the evolution of asymptotic wave function coefficients.
| [
{
"version": "v1",
"created": "Wed, 13 Oct 1999 14:14:53 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Aleixo",
"A. N. F.",
"",
"1 and 2"
],
[
"Balantekin",
"A. B.",
""
],
[
"Ribeiro",
"M. A. Candido",
""
]
] |
quant-ph/9910052 | Jonathan A. Jones | J. A. Jones, V. Vedral, A. Ekert and G. Castagnoli | Geometric quantum computation with NMR | Minor additions at request of referees. 4 pages revtex including 2
figures (1 eps). Nature in press | Nature 403 869-871 (2000) | 10.1038/35002528 | JAJQP-99-02 | quant-ph | null | The experimental realisation of the basic constituents of quantum information
processing devices, namely fault-tolerant quantum logic gates, requires
conditional quantum dynamics, in which one subsystem undergoes a coherent
evolution that depends on the quantum state of another subsystem. In
particular, the subsystem may acquire a conditional phase shift. Here we
consider a novel scenario in which this phase is of geometric rather than
dynamical origin. As the conditional geometric (Berry) phase depends only on
the geometry of the path executed it is resilient to certain types of errors,
and offers the potential of an intrinsically fault-tolerant way of performing
quantum gates. Nuclear Magnetic Resonance (NMR) has already been used to
demonstrate both simple quantum information processing and Berry's phase. Here
we report an NMR experiment which implements a conditional Berry phase, and
thus a controlled phase shift gate. This constitutes the first elementary
geometric quantum computation.
| [
{
"version": "v1",
"created": "Wed, 13 Oct 1999 16:56:58 GMT"
},
{
"version": "v2",
"created": "Wed, 5 Jan 2000 15:13:45 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Jones",
"J. A.",
""
],
[
"Vedral",
"V.",
""
],
[
"Ekert",
"A.",
""
],
[
"Castagnoli",
"G.",
""
]
] |
quant-ph/9910053 | Vadim Kostrykin | Vadim Kostrykin and Robert Schrader | Kirchhoff's Rule for Quantum Wires. II: The Inverse Problem with
Possible Applications to Quantum Computers | 16 pages | Fortschritte der Physik 48 (2000), 703 - 716 | 10.1002/1521-3978(200008)48:8<703::AID-PROP703>3.0.CO;2-O | null | quant-ph | null | In this article we continue our investigations of one particle quantum
scattering theory for Schroedinger operators on a set of connected (idealized
one-dimensional) wires forming a graph with an arbitrary number of open ends.
The Hamiltonian is given as minus the Laplace operator with suitable linear
boundary conditions at the vertices (the local Kirchhoff law). In ``Kirchhoff's
rule for quantum wires'' [J. Phys. A: Math. Gen. 32, 595 - 630 (1999)] we
provided an explicit algebraic expression for the resulting (on-shell) S-matrix
in terms of the boundary conditions and the lengths of the internal lines and
we also proved its unitarity. Here we address the inverse problem in the
simplest context with one vertex only but with an arbitrary number of open
ends. We provide an explicit formula for the boundary conditions in terms of
the S-matrix at a fixed, prescribed energy. We show that any unitary $n\times
n$ matrix may be realized as the S-matrix at a given energy by choosing
appropriate (unique) boundary conditions. This might possibly be used for the
design of elementary gates in quantum computing. As an illustration we
calculate the boundary conditions associated to the unitary operators of some
elementary gates for quantum computers and raise the issue whether in general
the unitary operators associated to quantum gates should rather be viewed as
scattering operators instead of time evolution operators for a given time
associated to a quantum mechanical Hamiltonian.
| [
{
"version": "v1",
"created": "Wed, 13 Oct 1999 18:40:37 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Kostrykin",
"Vadim",
""
],
[
"Schrader",
"Robert",
""
]
] |
quant-ph/9910054 | Tony Wong | T. Wong, Ozgur Mustecaplioglu, L. You and M. Lewenstein | Scattering of short laser pulses from trapped fermions | updated figures and revised content, submitted to Phys.Rev.A | null | 10.1103/PhysRevA.62.033608 | null | quant-ph cond-mat | null | We investigate the scattering of intense short laser pulses off trapped cold
fermionic atoms. We discuss the sensitivity of the scattered light to the
quantum statistics of the atoms. The temperature dependence of the scattered
light spectrum is calculated. Comparisons are made with a system of classical
atoms who obey Maxwell-Boltzmann statistics. We find the total scattering
increases as the fermions become cooler but eventually tails off at very low
temperatures (far below the Fermi temperature). At these low temperatures the
fermionic degeneracy plays an important role in the scattering as it inhibits
spontaneous emission into occupied energy levels below the Fermi surface. We
demonstrate temperature dependent qualitative changes in the differential and
total spectrum can be utilized to probe quantum degeneracy of trapped Fermi gas
when the total number of atoms are sufficiently large $(\geq 10^6)$. At smaller
number of atoms, incoherent scattering dominates and it displays weak
temperature dependence.
| [
{
"version": "v1",
"created": "Wed, 13 Oct 1999 20:33:29 GMT"
},
{
"version": "v2",
"created": "Thu, 4 Nov 1999 16:49:27 GMT"
},
{
"version": "v3",
"created": "Mon, 29 Nov 1999 19:27:11 GMT"
},
{
"version": "v4",
"created": "Tue, 28 Mar 2000 21:12:40 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Wong",
"T.",
""
],
[
"Mustecaplioglu",
"Ozgur",
""
],
[
"You",
"L.",
""
],
[
"Lewenstein",
"M.",
""
]
] |
quant-ph/9910055 | Eduardo Souza Fraga | C. A. A. de Carvalho, R. M. Cavalcanti, E. S. Fraga and S. E. Jor\'as | Semiclassical approximation to the partition function of a particle in D
dimensions | REVTEX,14 pages, 2 figures, final version to appear in Phys. Rev. E | Phys.Rev. E61 (2000) 6392 | 10.1103/PhysRevE.61.6392 | UCLA/99/TEP/33 | quant-ph cond-mat.stat-mech hep-ph hep-th | null | We use a path integral formalism to derive the semiclassical series for the
partition function of a particle in D dimensions. We analyze in particular the
case of attractive central potentials, obtaining explicit expressions for the
fluctuation determinant and for the semiclassical two-point function in the
special cases of the harmonic and single-well quartic anharmonic oscillators.
The specific heat of the latter is compared to precise WKB estimates. We
conclude by discussing the possible extension of our results to field theories.
| [
{
"version": "v1",
"created": "Wed, 13 Oct 1999 23:22:38 GMT"
},
{
"version": "v2",
"created": "Wed, 15 Mar 2000 01:01:05 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"de Carvalho",
"C. A. A.",
""
],
[
"Cavalcanti",
"R. M.",
""
],
[
"Fraga",
"E. S.",
""
],
[
"Jorás",
"S. E.",
""
]
] |
quant-ph/9910056 | Crispin Gardiner | C.W. Gardiner, J. Ye, H.C. Nagerl and H.J. Kimble | Evaluation of heating effects on atoms trapped in an optical trap | 3 pages TeX plus 4 postscript files | null | 10.1103/PhysRevA.61.045801 | null | quant-ph | null | We solve a stochastic master equation based on the theory of Savard et al.
[T.A. Savard, K.M. O'Hara and J.E. Thomas, Phys. Rev. A 56, R1095 (1997)] for
heating arising from fluctuations in the trapping laser intensity. We compare
with recent experiments of Ye et. al. [J. Ye, D.W. Vernooy and H.J. Kimble,
Trapping of single atoms in cavity QED, quant-ph/9908007, Phys. Rev. Lett.
(1999 in press)], and find good agreement with the experimental measurements of
the distribution of trap occupancy times. The major cause of trap loss arises
from the broadening of the energy distribution of the trapped atom, rather than
the mean heating rate, which is a very much smaller effect.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 01:09:38 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Gardiner",
"C. W.",
""
],
[
"Ye",
"J.",
""
],
[
"Nagerl",
"H. C.",
""
],
[
"Kimble",
"H. J.",
""
]
] |
quant-ph/9910057 | Bill Munro | W. J. Munro, G. J. Milburn and B. C. Sanders | Entangled Coherent State Qubits in an Ion Trap | 4 pages, No figures, accepted to PRA, minor change | Physical Review A 62, 052108 (2000). | 10.1103/PhysRevA.62.052108 | null | quant-ph | null | We show how entangled qubits can be encoded as entangled coherent states of
two-dimensional centre-of-mass vibrational motion for two ions in an ion trap.
The entangled qubit state is equivalent to the canonical Bell state, and we
introduce a proposal for entanglement transfer from the two vibrational modes
to the electronic states of the two ions in order for the Bell state to be
detected by resonance fluorescence shelving methods.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 01:17:46 GMT"
},
{
"version": "v2",
"created": "Mon, 7 Aug 2000 01:26:17 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Munro",
"W. J.",
""
],
[
"Milburn",
"G. J.",
""
],
[
"Sanders",
"B. C.",
""
]
] |
quant-ph/9910058 | Dagomir Kaszlikowski | Marek Zukowski, Dagomir Kaszlikowski, Adam Baturo and Jan-{\AA}ke
Larsson | Strengthening the Bell Theorem: conditions to falsify local realism in
an experiment | 4 pages, RevTex | null | null | null | quant-ph | null | The two-particle correlation obtained from the quantum state used in the Bell
inequality is sinusoidal, but the standard Bell inequality only uses two pairs
of settings and not the whole sinusoidal curve. The highest to-date visibility
of an explicit model reproducing sinusoidal fringes is 2/pi. We conjecture from
a numerical approach presented in this paper that the highest possible
visibility for a local hidden variable model reproducing the sinusoidal
character of the quantum prediction for the two-particle Bell-type interference
phenomena is 1/sqrt2. In addition, the approach can be applied directly to
experimental data.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 09:55:36 GMT"
}
] | 2022-03-16T00:00:00 | [
[
"Zukowski",
"Marek",
""
],
[
"Kaszlikowski",
"Dagomir",
""
],
[
"Baturo",
"Adam",
""
],
[
"Larsson",
"Jan-Åke",
""
]
] |
quant-ph/9910059 | Markus Grassl | Markus Grassl, Willi Geiselmann, and Thomas Beth (Universitaet
Karlsruhe) | Quantum Reed-Solomon Codes | Summary only (2 pages), for the full version see: Proceedings Applied
Algebra, Algebraic Algorithms and Error-Correcting Codes (AAECC-13), Lecture
Notes in Computer Science 1719, Springer, 1999 | null | 10.1007/3-540-46796-3_23 | null | quant-ph | null | After a brief introduction to both quantum computation and quantum error
correction, we show how to construct quantum error-correcting codes based on
classical BCH codes. With these codes, decoding can exploit additional
information about the position of errors. This error model - the quantum
erasure channel - is discussed. Finally, parameters of quantum BCH codes are
provided.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 10:56:26 GMT"
}
] | 2011-10-20T00:00:00 | [
[
"Grassl",
"Markus",
"",
"Universitaet\n Karlsruhe"
],
[
"Geiselmann",
"Willi",
"",
"Universitaet\n Karlsruhe"
],
[
"Beth",
"Thomas",
"",
"Universitaet\n Karlsruhe"
]
] |
quant-ph/9910060 | Markus Grassl | Markus Grassl and Thomas Beth (Universitaet Karlsruhe) | Quantum BCH Codes | null | Proceedings X. International Symposium on Theoretical Electrical
Engineering, Magdeburg, 1999, pp. 207-212 | null | null | quant-ph | null | After a brief introduction to both quantum computation and quantum error
correction, we show how to construct quantum error-correcting codes based on
classical BCH codes. With these codes, decoding can exploit additional
information about the position of errors. This error model - the quantum
erasure channel - is discussed. Finally, parameters of quantum BCH codes are
provided.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 13:10:06 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Grassl",
"Markus",
"",
"Universitaet Karlsruhe"
],
[
"Beth",
"Thomas",
"",
"Universitaet Karlsruhe"
]
] |
quant-ph/9910061 | Markus Grassl | Markus Grassl and Thomas Beth (Universitaet Karlsruhe) | Cyclic Quantum Error-Correcting Codes and Quantum Shift Registers | 18 pages, 15 figures, submitted to Proc. R. Soc. A | Proc. R. Soc. Lond. A (2000) 456, 2689-2706 | 10.1098/rspa.2000.0633 | null | quant-ph | null | We transfer the concept of linear feed-back shift registers to quantum
circuits. It is shown how to use these quantum linear shift registers for
encoding and decoding cyclic quantum error-correcting codes.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 11:09:17 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Grassl",
"Markus",
"",
"Universitaet Karlsruhe"
],
[
"Beth",
"Thomas",
"",
"Universitaet Karlsruhe"
]
] |
quant-ph/9910062 | Izumi Tsutsui | Tamas Fulop and Izumi Tsutsui | A Free Particle on a Circle with Point Interaction | Plain TeX, 14 pages | null | 10.1016/S0375-9601(99)00850-6 | KEK Preprint 99-115 | quant-ph math-ph math.MP | null | The quantum dynamics of a free particle on a circle with point interaction is
described by a U(2) family of self-adjoint Hamiltonians. We provide a
classification of the family by introducing a number of subfamilies and thereby
analyze the spectral structure in detail. We find that the spectrum depends on
a subset of U(2) parameters rather than the entire U(2) needed for the
Hamiltonians, and that in particular there exists a subfamily in U(2) where the
spectrum becomes parameter-independent. We also show that, in some specific
cases, the WKB semiclassical approximation becomes exact (modulo phases) for
the system.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 11:34:26 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Fulop",
"Tamas",
""
],
[
"Tsutsui",
"Izumi",
""
]
] |
quant-ph/9910063 | Michael M. Wolf | Reinhard F. Werner and Michael M. Wolf | Bell's inequalities for states with positive partial transpose | 4 pages, REVTeX | Phys. Rev. A 61, 062102 (2000) | 10.1103/PhysRevA.61.062102 | null | quant-ph | null | We study violations of n particle Bell inequalities (as developed by Mermin
and Klyshko) under the assumption that suitable partial transposes of the
density operator are positive. If all transposes with respect to a partition of
the system into p subsystems are positive, the best upper bound on the
violation is 2^((n-p)/2). In particular, if the partial transposes with respect
to all subsystems are positive, the inequalities are satisfied. This is
supporting evidence for a recent conjecture by Peres that positivity of partial
transposes could be equivalent to existence of local classical models.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 13:01:49 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Werner",
"Reinhard F.",
""
],
[
"Wolf",
"Michael M.",
""
]
] |
quant-ph/9910064 | Kal Gerd Vollbrecht | K.G.H. Vollbrecht and R.F. Werner | Why Two Qubits Are Special | 16 pages, TeX | null | 10.1063/1.1286032 | null | quant-ph | null | We analyze some special properties of a system of two qubits, and in
particular of the so-called Bell basis for this system, which have played an
important role in recent papers on entanglement of qubits. In particular, we
show which of these properties may be generalized to higher dimension. We give
a general construction for bases of maximally entangled vectors in any
dimension, but show that none of the properties related to complex conjugation
in Bell basis can be realized for higher dimensional analogs.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 14:01:40 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Vollbrecht",
"K. G. H.",
""
],
[
"Werner",
"R. F.",
""
]
] |
quant-ph/9910065 | Carlo Presilla | Fabrizio Cametti, Giovanni Jona-Lasinio, Carlo Presilla, Fabio
Toninelli | Comparison between quantum and classical dynamics in the effective
action formalism | 18 pages, 2 figures, contribution to the proceedings of the
International School of Physics ``Enrico Fermi'', Course CXLIII | Proceedings of the International School of Physics ``Enrico
Fermi'', Course CXLIII, edited by G. Casati, I. Guarneri, U. Smilansky (IOS
Press, Amsterdam 2000), p. 431-448. | null | null | quant-ph chao-dyn cond-mat nlin.CD | null | No abstract available
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 15:39:45 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Cametti",
"Fabrizio",
""
],
[
"Jona-Lasinio",
"Giovanni",
""
],
[
"Presilla",
"Carlo",
""
],
[
"Toninelli",
"Fabio",
""
]
] |
quant-ph/9910066 | Maria A. Lledo | Richard Arens, V. S. Varadarajan | On the concept of EPR states and their structure | Plain TeX, 22 pages | Journal of Mathematical Physics, vol. 41, n. 2 (2000) 638. | 10.1063/1.533156 | null | quant-ph | null | In this paper the notion of an EPR state for the composite S of two quantum
systems S1, S2, relative to S2 and a set O of bounded observables of S2, is
introduced in the spirit of classical examples of Einstein-Podolsky-Rosen and
Bohm. We restrict ourselves mostly to EPR states of finite norm. The main
results are contained in Theorem 3,4,5,6 in section III and imply that if the
EPR states of finite norm relative to (S2, O) exist, then the elements of O
have discrete probability distributions and the Von Neuman algebra generated by
O is essentially inbeddable inside S1 by an antiunitary map. The EPR states
then correspond to the different imbeddings and certain additional parameters,
and are explicitely given by formulae which generalize the famous example of
Bohm. If O generates all bounded observables, S2 must be of finite dimension
and can be imbedded inside S1 by an antiunitary map, and the EPR states
relative to S2 are then in canonical bijection with the different imbeddings of
S2 inside S1; moreover they are given by formulae which are exactly those of
the generalized Bohm states. The notion of EPR states of infinite norm is also
explored and it is shown that the original state of Einstein-Podolsky-Rosen can
be realized as a renormalized limit of EPR states of finite quantum systems
considered by Weyl, Schwinger and many others. Finally, a family of states of
infinite norm generalizing the Einstein-Podolsky-Rosen example is explicitly
given.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 17:17:34 GMT"
},
{
"version": "v2",
"created": "Fri, 15 Oct 1999 10:05:08 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Arens",
"Richard",
""
],
[
"Varadarajan",
"V. S.",
""
]
] |
quant-ph/9910067 | Daniel Gottesman | Daniel Gottesman | On the Theory of Quantum Secret Sharing | 9 pages, REVTeX | Phys. Rev. A 61, 042311 (2000) | 10.1103/PhysRevA.61.042311 | null | quant-ph | null | I present a variety of results on the theory of quantum secret sharing. I
show that any mixed state quantum secret sharing scheme can be derived by
discarding a share from a pure state scheme, and that the size of each share in
a quantum secret sharing scheme must be at least as large as the size of the
secret. I show that the only constraints on the existence of quantum secret
sharing schemes with general access structures are monotonicity (if a set is
authorized, so are larger sets) and the no-cloning theorem. I also discuss some
aspects of sharing classical secrets using quantum states. In this situation,
the size of each share can sometimes be half the size of the classical secret.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 19:00:54 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Gottesman",
"Daniel",
""
]
] |
quant-ph/9910068 | Ilki Kim | Ilki Kim, Guenter Mahler | Quantum chaos in quantum Turing machines | Accepted for publication in Phys. Lett. A, 3 figures | null | 10.1016/S0375-9601(99)00720-3 | null | quant-ph | null | We investigate a 2-spin quantum Turing architecture, in which discrete local
rotations \alpha_m of the Turing head spin alternate with quantum controlled
NOT-operations. We demonstrate that a single chaotic parameter input \alpha_m
leads to a chaotic dynamics in the entire Hilbert-space.
| [
{
"version": "v1",
"created": "Thu, 14 Oct 1999 23:14:01 GMT"
},
{
"version": "v2",
"created": "Mon, 18 Oct 1999 15:29:02 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Kim",
"Ilki",
""
],
[
"Mahler",
"Guenter",
""
]
] |
quant-ph/9910069 | Kazuyuki Fujii | Kazuyuki Fujii | Note on Coherent States and Adiabatic Connections, Curvatures | Latex file, 12 pages | J.Math.Phys. 41 (2000) 4406-4412 | 10.1063/1.533350 | null | quant-ph hep-th math-ph math.MP | null | We give a possible generalization to the example in the paper of Zanardi and
Rasetti (quant-ph/9904011). For this generalized one explicit forms of
adiabatic connection, curvature and etc. are given.
| [
{
"version": "v1",
"created": "Fri, 15 Oct 1999 01:46:04 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Fujii",
"Kazuyuki",
""
]
] |
quant-ph/9910070 | Fabrizio Illuminati | N. Cufaro Petroni, S. De Martino, S. De Siena, and F. Illuminati | Controlled quantum evolutions and transitions | 24 pages, 4 figures | J. Phys. A 32, 7489-7508 (1999) | 10.1088/0305-4470/32/43/305 | null | quant-ph | null | We study the nonstationary solutions of Fokker-Planck equations associated to
either stationary or nonstationary quantum states. In particular we discuss the
stationary states of quantum systems with singular velocity fields. We
introduce a technique that allows to realize arbitrary evolutions ruled by
these equations, to account for controlled quantum transitions. The method is
illustrated by presenting the detailed treatment of the transition
probabilities and of the controlling time-dependent potentials associated to
the transitions between the stationary, the coherent, and the squeezed states
of the harmonic oscillator. Possible extensions to anharmonic systems and mixed
states are briefly discussed and assessed.
| [
{
"version": "v1",
"created": "Fri, 15 Oct 1999 10:11:55 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Petroni",
"N. Cufaro",
""
],
[
"De Martino",
"S.",
""
],
[
"De Siena",
"S.",
""
],
[
"Illuminati",
"F.",
""
]
] |
quant-ph/9910071 | Rajkumar Roychoudhury | A.Sinha and R.Roychoudhury | WKB and MAF Quantization Rules for Spatially Confined Quantum Mechanical
Systems | null | Int.J.Quant.Chemistry 73 (1999) 497 | null | null | quant-ph | null | A formalism is developed to obtain the energy eigenvalues of spatially
confined quantum mechanical systems in the framework of The usual WKB and MAF
methods. The technique is applied to three different cases,viz one dimensional
Harmonic Oscillators,Quartic Oscillators and a boxed-in charged particle in
electric field.
| [
{
"version": "v1",
"created": "Fri, 15 Oct 1999 12:53:44 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sinha",
"A.",
""
],
[
"Roychoudhury",
"R.",
""
]
] |
quant-ph/9910072 | Howard N. Barnum | Howard N. Barnum | Quantum secure identification using entanglement and catalysis | 7 pages; no figures | null | null | null | quant-ph | null | I consider the use of entanglement between two parties to enable one to
authenticate her identity to another over a quantum communication channel.
Exploiting the phenomenon of entanglement-catalyzed transformations between
pure states gives a potentially reusable entangled identification token. In
analyzing this, I consider the independently interesting problem of the best
possible approximation to a given pure entangled state realizable using local
actions and classical communication by parties sharing a different entangled
state.
| [
{
"version": "v1",
"created": "Fri, 15 Oct 1999 15:52:35 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Barnum",
"Howard N.",
""
]
] |
quant-ph/9910073 | Yu Shi | Yu Shi | Entanglement Between Bose-Einstein Condensates | 18 pages. Eq. (73) is changed | Int. J. Mod. Phys. B, Vol. 15 (2001) 3007-3030 | 10.1142/S0217979201007154 | null | quant-ph | null | For a Bose condensate in a double-well potential or with two
Josephson-coupled internal states, the condensate wavefunction is a
superposition. Here we consider coupling two such Bose condensates, and suggest
the existence of a joint condensate wavefunction, which is in general a
superposition of all products of the bases condensate wavefunctions of the two
condensates. The corresponding many-body state is a product of such superposed
wavefunctions, with appropriate symmetrization. These states may be potentially
useful for quantum computation. There may be robustness and stability due to
macroscopic occupation of a same single particle state. The nonlinearity of the
condensate wavefunction due to particle-particle interaction may be utilized to
realize nonlinear quantum computation, which was suggested to be capable of
solving NP-complete problems.
| [
{
"version": "v1",
"created": "Fri, 15 Oct 1999 16:32:13 GMT"
},
{
"version": "v2",
"created": "Sun, 17 Oct 1999 23:52:34 GMT"
},
{
"version": "v3",
"created": "Wed, 20 Oct 1999 00:07:10 GMT"
},
{
"version": "v4",
"created": "Tue, 1 Feb 2000 16:11:38 GMT"
},
{
"version": "v5",
"created": "Tue, 27 Jun 2000 21:53:24 GMT"
},
{
"version": "v6",
"created": "Sat, 9 Jun 2001 21:53:01 GMT"
},
{
"version": "v7",
"created": "Mon, 20 Aug 2001 10:03:38 GMT"
},
{
"version": "v8",
"created": "Thu, 27 Jun 2002 10:02:26 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Shi",
"Yu",
""
]
] |
quant-ph/9910074 | Euro Spallucci | S.Ansoldi, A.Aurilia, E.Spallucci | Particle Propagator in Elementary Quantum Mechanics: a New Path Integral
Derivation | LaTex uses iopams package, 15pages, no figures, in print on Euro.J.of
Phys | Eur.J.Phys. 21 (2000) 1-12 | 10.1088/0143-0807/21/1/301 | null | quant-ph hep-th | null | This paper suggests a new way to compute the path integral for simple quantum
mechanical systems. The new algorithm originated from previous research in
string theory. However, its essential simplicity is best illustrated in the
case of a free non relativistic particle, discussed here, and can be
appreciated by most students taking an introductory course in Quantum
Mechanics. Indeed, the emphasis is on the role played by the {\it entire family
of classical trajectories} in terms of which the path integral is computed
exactly using a functional representation of the Dirac delta-distribution. We
argue that the new algorithm leads to a deeper insight into the connection
between classical and quantum systems, especially those encountered in high
energy physics.
| [
{
"version": "v1",
"created": "Sat, 16 Oct 1999 08:30:01 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Ansoldi",
"S.",
""
],
[
"Aurilia",
"A.",
""
],
[
"Spallucci",
"E.",
""
]
] |
quant-ph/9910075 | Lieven Vandersypen | Lieven M.K. Vandersypen (1 and 2), Matthias Steffen (1 and 2), Mark H.
Sherwood (2), Costantino S. Yannoni (2), Gregory Breyta (2) and Isaac L.
Chuang (2) ((1) Solid State and Photonics Laboratory, Stanford University (2)
IBM Almaden Research Center) | Implementation of a three-quantum-bit search algorithm | Published in Applied Physics Letters, vol. 76, no. 5, 31 January
2000, p.646-648, after minor revisions. (revtex, mypsfig2.sty, 3 figures) | null | 10.1063/1.125846 | null | quant-ph | null | We report the experimental implementation of Grover's quantum search
algorithm on a quantum computer with three quantum bits. The computer consists
of molecules of $^{13}$C-labeled CHFBr$_2$, in which the three weakly coupled
spin-1/2 nuclei behave as the bits and are initialized, manipulated, and read
out using magnetic resonance techniques. This quantum computation is made
possible by the introduction of two techniques which significantly reduce the
complexity of the experiment and by the surprising degree of cancellation of
systematic errors which have previously limited the total possible number of
quantum gates.
| [
{
"version": "v1",
"created": "Sat, 16 Oct 1999 21:51:41 GMT"
},
{
"version": "v2",
"created": "Tue, 1 Feb 2000 20:22:08 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Vandersypen",
"Lieven M. K.",
"",
"1 and 2"
],
[
"Steffen",
"Matthias",
"",
"1 and 2"
],
[
"Sherwood",
"Mark H.",
""
],
[
"Yannoni",
"Costantino S.",
""
],
[
"Breyta",
"Gregory",
""
],
[
"Chuang",
"Isaac L.",
""
]
] |
quant-ph/9910076 | Gui Lu Long | Gui Lu Long, Yan Song Li, Wei Lin Zhang and Chang Cun Tu | An intrinsic limitation on the size of quantum database | 6 pages, 3 figures | null | null | null | quant-ph | null | It is found that Grover's quantum search algorithm is not robust against
phase inversion and Hadmard transformation inaccuracies. Imperfect phase
inversions and Hadmard-Walsh transformations in Grover's quantum search
algorithm lead to reductions in the maximum probability of the marked state and
affect the efficiency of the algorithm. even in the absence of decoherence.
Given the degrees of inaccuracies, we find that to guarantee half rate of
success, the size of the database should be in the order of $O({1 \over
\delta^2})$, where $\delta$ is the uncertainty.
| [
{
"version": "v1",
"created": "Sat, 16 Oct 1999 23:51:40 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Long",
"Gui Lu",
""
],
[
"Li",
"Yan Song",
""
],
[
"Zhang",
"Wei Lin",
""
],
[
"Tu",
"Chang Cun",
""
]
] |
quant-ph/9910077 | Reinhard Werner | R.F. Werner (Inst. Math. Phys., TU-Braunschweig) | EPR states for von Neumann algebras | 2 pages, RevTeX | null | null | TUBS/IMaPh-99-xx | quant-ph | null | In a recent paper [quant-ph/9910066], Arens and Varadarajan gave a
characterization of what they call EPR-states on a bipartite composite quantum
system. By definition, such states imply perfect correlation between suitable
pairs of observables in the two subsystems, and the task is to determine all
such correlated pairs for a given state. In this note the argument is shortened
and simplified, and at the same time extended to observables in general von
Neumann algebras, which naturally arise in quantum field theory.
| [
{
"version": "v1",
"created": "Sun, 17 Oct 1999 22:26:27 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Werner",
"R. F.",
"",
"Inst. Math. Phys., TU-Braunschweig"
]
] |
quant-ph/9910078 | Asher Peres | Asher Peres | Popper's experiment and the Copenhagen interpretation | 13 pages LaTeX, one separate page of figures, submitted to SHPMP | Stud. History Philos. Modern Physics 33 (2002) 23 | null | null | quant-ph | null | Popper conceived an experiment whose analysis led to a result that he deemed
absurd. Popper wrote that his reasoning was based on the Copenhagen
interpretation and therefore invalidated the latter. Actually, Popper's
argument involves counterfactual reasoning and violates Bohr's complementarity
principle. The absurdity of Popper's result only confirms Bohr's approach.
| [
{
"version": "v1",
"created": "Mon, 18 Oct 1999 08:16:30 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Peres",
"Asher",
""
]
] |
quant-ph/9910079 | Bjorn Jensen | B. Jensen and I. Brevik | Transition Radiation and the Origin of Sonoluminescence | 13 pages. Discussion improved and references added. To appear in
Phys. Rev. E | Phys.Rev.E61:6639,2000 | 10.1103/PhysRevE.61.6639 | null | quant-ph hep-th physics.flu-dyn | null | It has been shown by Liberati et al. [quant-ph/9904013] that a dielectric
medium with a time-dependent refractive index may produce photons. We point out
that a free electric charge which interacts with such a medium will emit
quantum mechanically modified transition radiation in which an arbitrary odd
number of photons will be present. Excited atomic electrons will also exhibit a
similarly modified emission spectrum. This effect may be directly observable in
connection with sonoluminescence.
| [
{
"version": "v1",
"created": "Mon, 18 Oct 1999 21:12:00 GMT"
},
{
"version": "v2",
"created": "Mon, 20 Mar 2000 11:51:45 GMT"
}
] | 2009-01-14T00:00:00 | [
[
"Jensen",
"B.",
""
],
[
"Brevik",
"I.",
""
]
] |
quant-ph/9910080 | Mark M. Mims | V. I. Man'ko, G. Marmo, E. C. G. Sudarshan, and F. Zaccaria | Purification of impure density operators and the recovery of
entanglements | 6 pages | null | null | CPP-99-17 | quant-ph | null | The need to retain the relative phases in quantum mechanics implies an
addition law parametrized by a phase of two density operators required for the
purification of a density matrix. This is shown with quantum tomography and the
Wigner function. Entanglement is determined in terms of phase dependent
multiplication.
| [
{
"version": "v1",
"created": "Mon, 18 Oct 1999 21:14:32 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Man'ko",
"V. I.",
""
],
[
"Marmo",
"G.",
""
],
[
"Sudarshan",
"E. C. G.",
""
],
[
"Zaccaria",
"F.",
""
]
] |
quant-ph/9910081 | Dorit Aharonov | Dorit Aharonov | A Quantum to Classical Phase Transition in Noisy Quantum Computers | 15 pages. Latex2e plus one figure in eps file | null | 10.1103/PhysRevA.62.062311 | null | quant-ph | null | The fundamental problem of the transition from quantum to classical physics
is usually explained by decoherence, and viewed as a gradual process. The study
of entanglement, or quantum correlations, in noisy quantum computers implies
that in some cases the transition from quantum to classical is actually a phase
transition. We define the notion of entanglement length in $d$-dimensional
noisy quantum computers, and show that a phase transition in entanglement
occurs at a critical noise rate, where the entanglement length transforms from
infinite to finite. Above the critical noise rate, macroscopic classical
behavior is expected, whereas below the critical noise rate, subsystems which
are macroscopically distant one from another can be entangled.
The macroscopic classical behavior in the super-critical phase is shown to
hold not only for quantum computers, but for any quantum system composed of
macroscopically many finite state particles, with local interactions and local
decoherence, subjected to some additional conditions.
This phenomenon provides a possible explanation to the emergence of classical
behavior in such systems. A simple formula for an upper bound on the
entanglement length of any such system in the super-critical phase is given,
which can be tested experimentally.
| [
{
"version": "v1",
"created": "Tue, 19 Oct 1999 02:19:39 GMT"
}
] | 2016-09-08T00:00:00 | [
[
"Aharonov",
"Dorit",
""
]
] |
quant-ph/9910082 | Larry Horwitz | Y. Strauss and L.P. Horwitz | Representation of the Resonances of a Relativistic Quantum Field
Theoretical Model in Lax-Phillips Scattering Theory | Tex, 15 pages, report TAUP 2588-99. Proceedings of Solvay Conference
Les Treilles 3-8 July, 1999. To be published in Chaos, Solitons and Fractals | null | null | null | quant-ph | null | We apply the quantum Lax-Phillips scattering theory to a relativistically
covariant quantum field theoretical form of the (soluble) Lee model. We
construct the translation representations with the help of the wave operators,
and show that the resulting Lax-Phillips $S$-matrix is an inner function (the
Lax-Phillips theory is essentially a theory of translation invariant
subspaces). We then discuss the non-relativistic limit of this theory, and show
that the resulting kinematic relations coincide with the conditions required
for the Galilean description of a decaying system.
| [
{
"version": "v1",
"created": "Tue, 19 Oct 1999 16:11:41 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Strauss",
"Y.",
""
],
[
"Horwitz",
"L. P.",
""
]
] |
quant-ph/9910083 | Marcelo Aparecido Marchiolli | Marcelo A. Marchiolli, Salomon S. Mizrahi, Victor V. Dodonov | Marginal and correlation distribution functions in the squeezed-states
representation | 11 pages, 12 EPS figures, figures 1(a)-(d) can be obtained with the
first author, accepted for publication in Journal Physics A | null | 10.1088/0305-4470/32/49/311 | null | quant-ph | null | Here we consider the Husimi function P for the squeezed states and calculate
the marginal and correlation distribution functions when P is projected onto
the photon number states. According to the value of the squeezing parameter one
verifies the occurence of oscillations and beats as already appointed in the
literature. We verify that these phenomena are entirely contained in the
correlation function. In particular, we show that since Husimi and its marginal
distribution functions satisfy partial differential equations where the squeeze
parameter plays the role of time, the solutions (the squeezed functions
obtained from initial unsqueezed functions) can be expressed by means of
kernels responsible for the propagation of squeezing. From the calculational
point of view, this method presents advantages for calculating the marginal
distribution functions (compared to a direct integration over one of the two
phase-space variables of P) since one can use the symmetry properties of the
differential equations.
| [
{
"version": "v1",
"created": "Tue, 19 Oct 1999 18:20:39 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Marchiolli",
"Marcelo A.",
""
],
[
"Mizrahi",
"Salomon S.",
""
],
[
"Dodonov",
"Victor V.",
""
]
] |
quant-ph/9910084 | Pieter Kok | Pieter Kok and Samuel L. Braunstein | Detection devices in entanglement-based optical state preparation | 8 pages, 4 figures REVTeX | Phys. Rev. A 63, 033812 (2001) | 10.1103/PhysRevA.63.033812 | null | quant-ph | null | We study the use of detection devices in entanglement-based state
preparation. In particular we consider optical detection devices such as
single-photon sensitivity detectors, single-photon resolution detectors and
detector cascades (with an emphasis on the performance of realistic detectors).
We develop an extensive theory for the use of these devices. In
entanglement-based state preparation we perform measurements on subsystems, and
we therefore need precise bounds on the distinguishability of these
measurements (this is fundamentally different from, e.g., tomography, where an
ensemble of identical states is used to determine probability distributions,
etc.). To this end, we introduce the confidence of preparation, which may also
be used to quantify the performance of detection devices in entanglement-based
preparation. We give a general expression for detector cascades of arbitrary
size for the detection up to two photons. We show that, contrary to the general
belief, cascading does not give a practical advantage over detectors with
single-photon resolution in entanglement-based state preparation.
| [
{
"version": "v1",
"created": "Wed, 20 Oct 1999 12:08:17 GMT"
},
{
"version": "v2",
"created": "Tue, 20 Feb 2001 12:00:37 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Kok",
"Pieter",
""
],
[
"Braunstein",
"Samuel L.",
""
]
] |
quant-ph/9910085 | Massimiliano F. Sacchi | G. Mauro D'Ariano, Massimiliano F. Sacchi, Prem Kumar | Universal homodyne tomography with a single local oscillator | 12 pages, 5 figures (8 eps files) | Phys. Rev. A, 61, 013806 (2000). | 10.1103/PhysRevA.61.013806 | null | quant-ph | null | We propose a general method for measuring an arbitrary observable of a
multimode electromagnetic field using homodyne detection with a single local
oscillator. In this method the local oscillator scans over all possible linear
combinations of the modes. The case of two modes is analyzed in detail and the
feasibility of the measurement is studied on the basis of Monte-Carlo
simulations. We also provide an application of this method in tomographic
testing of the GHZ state.
| [
{
"version": "v1",
"created": "Wed, 20 Oct 1999 12:41:19 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"D'Ariano",
"G. Mauro",
""
],
[
"Sacchi",
"Massimiliano F.",
""
],
[
"Kumar",
"Prem",
""
]
] |
quant-ph/9910086 | Martin Plenio | Martin B. Plenio (Imperial College, London, UK) | The Holevo bound and Landauer's principle | to appear in Physics Letters A | Phys. Lett. A 263, 281 - 284 (1999) | 10.1016/S0375-9601(99)00737-9 | null | quant-ph | null | Landauer's principle states that the erasure of information generates a
corresponding amount of entropy in the environment. We show that Landauer's
principle provides an intuitive basis for Holevo bound on the classical
capacity of a quantum channel.
| [
{
"version": "v1",
"created": "Wed, 20 Oct 1999 13:36:39 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Plenio",
"Martin B.",
"",
"Imperial College, London, UK"
]
] |
quant-ph/9910087 | Adrian Kent | Adrian Kent (DAMTP, University of Cambridge) | Unconditionally Secure Commitment of a Certified Classical Bit is
Impossible | 5 pages, RevTeX. Minor clarification made distinguishing proper and
improper mixed state commitments | Phys. Rev. A 61, 042301 (2000) | 10.1103/PhysRevA.61.042301 | DAMTP-1999-51 | quant-ph cs.CR | null | In a secure bit commitment protocol involving only classical physics, A
commits either a 0 or a 1 to B. If quantum information is used in the protocol,
A may be able to commit a state of the form $\alpha \ket{0} + \beta \ket{1}$.
If so, she can also commit mixed states in which the committed bit is entangled
with other quantum states under her control. We introduce here a quantum
cryptographic primitive, {\it bit commitment with a certificate of
classicality} (BCCC), which differs from standard bit commitment in that it
guarantees that the committed state has a fixed classical value. We show that
no unconditionally secure BCCC protocol based on special relativity and quantum
theory exists. We also propose complete definitions of security for quantum and
relativistic bit commitment.
| [
{
"version": "v1",
"created": "Wed, 20 Oct 1999 21:09:56 GMT"
},
{
"version": "v2",
"created": "Wed, 3 Nov 1999 21:15:11 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Kent",
"Adrian",
"",
"DAMTP, University of Cambridge"
]
] |
quant-ph/9910088 | Karol Zyczkowski | Karol Zyczkowski (Cracow/Warsaw) | Localization of Eigenstates & Mean Wehrl Entropy | 7 pages in Latex with 4 pictures in .ps (included), submitted to
Physica E | Physica E 9, 583 (2001) | 10.1016/S1386-9477(00)00266-6 | null | quant-ph chao-dyn nlin.CD | null | Dynamics of a periodically time dependent quantum system is reflected in the
features of the eigenstates of the Floquet operator. Of the special importance
are their localization properties quantitatively characterized by the
eigenvector entropy, the inverse participation ratio or the eigenvector
statistics. Since these quantities depend on the choice of the eigenbasis, we
suggest to use the overcomplete basis of coherent states, uniquely determined
by the classical phase space. In this way we define the mean Wehrl entropy of
eigenvectors of the Floquet operator and demonstrate that this quantity is
useful to describe quantum chaotic systems.
| [
{
"version": "v1",
"created": "Thu, 21 Oct 1999 15:24:01 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Zyczkowski",
"Karol",
"",
"Cracow/Warsaw"
]
] |
quant-ph/9910089 | An Min Wang | An Min Wang | An Universal Quantum Network - Quantum CPU | 8 pages, Revised version | Cheses Phys. Lett. Vol.18 p166 (2001) [ been shorten and revised] | 10.1088/0256-307X/18/2/304 | null | quant-ph | null | An universal quantum network which can implement a general quantum computing
is proposed. In this sense, it can be called the quantum central processing
unit (QCPU). For a given quantum computing, its realization of QCPU is just its
quantum network. QCPU is standard and easy-assemble because it only has two
kinds of basic elements and two auxiliary elements. QCPU and its realizations
are scalable, that is, they can be connected together, and so they can
construct the whole quantum network to implement the general quantum algorithm
and quantum simulating procedure.
| [
{
"version": "v1",
"created": "Thu, 21 Oct 1999 18:34:58 GMT"
},
{
"version": "v2",
"created": "Mon, 1 Nov 1999 09:36:36 GMT"
},
{
"version": "v3",
"created": "Mon, 3 Jan 2000 12:13:35 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Wang",
"An Min",
""
]
] |
quant-ph/9910090 | An Min Wang | An Min Wang | Quantum CPU and Quantum Simulating | 8 pages, Revised Version | null | null | null | quant-ph | null | Making use of an universal quantum network or QCPU proposed by me [6], some
special quantum networks for simulating some quantum systems are given out.
Specially, it is obtained that the quantum network for the time evolution
operator which can simulate, in general, Schr\"odinger equation.
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 09:57:52 GMT"
},
{
"version": "v2",
"created": "Mon, 1 Nov 1999 09:47:36 GMT"
},
{
"version": "v3",
"created": "Mon, 3 Jan 2000 12:25:25 GMT"
}
] | 2009-09-25T00:00:00 | [
[
"Wang",
"An Min",
""
]
] |
quant-ph/9910091 | An Min Wang | An Min Wang | Quantum CPU and Quantum Algorithm | 8 pages, Revised Version | Cheses Phys. Lett. Vol.19 p620 (2002) [ been shorten and revised] | 10.1088/0256-307X/19/5/304 | null | quant-ph | null | Making use of an universal quantum network -- QCPU proposed by
me\upcite{My1}, it is obtained that the whole quantum network which can
implement some the known quantum algorithms including Deutsch algorithm,
quantum Fourier transformation, Shor's algorithm and Grover's algorithm.
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 10:09:02 GMT"
},
{
"version": "v2",
"created": "Mon, 1 Nov 1999 09:56:36 GMT"
},
{
"version": "v3",
"created": "Mon, 3 Jan 2000 12:29:55 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Wang",
"An Min",
""
]
] |
quant-ph/9910092 | Jaroslav Rehacek | J. Rehacek, Z. Hradil, M. Dusek, O. Haderka and M. Hendrych | Testing operational phase concepts in quantum optics | 8 pages, 6 figures | null | 10.1088/1464-4266/2/3/304 | null | quant-ph | null | An experimental comparison of several operational phase concepts is
presented. In particular, it is shown that statistically motivated evaluation
of experimental data may lead to a significant improvement in phase fitting
upon the conventional Noh, Fouge'res and Mandel procedure. The analysis is
extended to the asymptotic limit of large intensities, where a strong evidence
in favor of multi--dimensional estimation procedures has been found.
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 13:23:22 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Rehacek",
"J.",
""
],
[
"Hradil",
"Z.",
""
],
[
"Dusek",
"M.",
""
],
[
"Haderka",
"O.",
""
],
[
"Hendrych",
"M.",
""
]
] |
quant-ph/9910093 | Norbert Luetkenhaus | Norbert L\"utkenhaus | Security against individual attacks for realistic quantum key
distribution | 10 pages, 4 figures | Physical Review A, Vol. 61, 052304 (2000) | 10.1103/PhysRevA.61.052304 | null | quant-ph | null | I prove the security of quantum key distribution against individual attacks
for realistic signals sources, including weak coherent pulses and
downconversion sources. The proof applies to the BB84 protocol with the
standard detection scheme (no strong reference pulse). I obtain a formula for
the secure bit rate per time slot of an experimental setup which can be used to
optimize the performance of existing schemes for the considered scenario.
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 16:11:41 GMT"
},
{
"version": "v2",
"created": "Wed, 2 Feb 2000 15:05:18 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Lütkenhaus",
"Norbert",
""
]
] |
quant-ph/9910094 | Mikhail Lukin | M.D.Lukin and A.Imamoglu | Nonlinear Optics and Quantum Entanglement of Ultra-Slow Single Photons | null | null | 10.1103/PhysRevLett.84.1419 | null | quant-ph | null | Two light pulses propagating with ultra-slow group velocities in a coherently
prepared atomic gas exhibit dissipation-free nonlinear coupling of an
unprecedented strength. This enables a single-photon pulse to coherently
control or manipulate the quantum state of the other. Processes of this kind
result in generation of entangled states of radiation field and open up new
prospectives for quantum information processing.
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 18:01:52 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Lukin",
"M. D.",
""
],
[
"Imamoglu",
"A.",
""
]
] |
quant-ph/9910095 | H. Bechmann-Pasquinucci | H. Bechmann-Pasquinucci, W. Tittel | Quantum Cryptography using larger alphabets | 12 pages, 2 (eps) figures | null | 10.1103/PhysRevA.61.062308 | null | quant-ph | null | Like all of quantum information theory, quantum cryptography is traditionally
based on two level quantum systems. In this letter, a new protocol for quantum
key distribution based on higher dimensional systems is presented. An
experimental realization using an interferometric setup is also proposed.
Analyzing this protocol from the practical side, one finds an increased key
creation rate while keeping the initial laser pulse rate constant. Analyzing it
for the case of intercept/resend eavesdropping strategy, an increased error
rate is found compared to two dimensional systems, hence an advantage for the
legitimate users to detect an eavesdropper.
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 18:46:43 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Bechmann-Pasquinucci",
"H.",
""
],
[
"Tittel",
"W.",
""
]
] |
quant-ph/9910096 | Jeffrey Bub | Jeffrey Bub | Quantum Mechanics as a Principle Theory | 26 pages, no figures, LaTeX. Forthcoming March 2000 in Studies in the
History and Philosophy of Modern Physics | Studies in History and Philosophy of Modern Physics 31 (2000) 75 | null | null | quant-ph | null | I show how quantum mechanics, like the theory of relativity, can be
understood as a 'principle theory' in Einstein's sense, and I use this notion
to explore the approach to the problem of interpretation developed in my book
Interpreting the Quantum World (Cambridge: Cambridge University Press, 1999).
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 23:40:57 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bub",
"Jeffrey",
""
]
] |
quant-ph/9910097 | Jeffrey Bub | Jeffrey Bub, Rob Clifton, Sheldon Goldstein | Revised Proof of the Uniqueness Theorem for 'No Collapse'
Interpretations of Quantum Mechanics | 5 pages, LaTeX. Forthcoming March 2000 in Studies in the History and
Philosophy of Modern Physics | Studies in History and Philosophy of Modern Physics 31 (2000) 95 | null | null | quant-ph | null | We show that the Bub-Clifton uniqueness theorem for 'no collapse'
interpretations of quantum mechanics (Studies in the History and Philosophy of
Modern Physics 27, 181-219 (1996)) can be proved without the 'weak
separability' assumption.
| [
{
"version": "v1",
"created": "Fri, 22 Oct 1999 23:52:51 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Bub",
"Jeffrey",
""
],
[
"Clifton",
"Rob",
""
],
[
"Goldstein",
"Sheldon",
""
]
] |
quant-ph/9910098 | Xiao-Guang Wang | Xiao-Guang Wang and Hong-Chen Fu | Statistical Properties and Algebraic Characteristics of Quantum
Superpositions of Negative Binomial States | 11 pages and 2 figures | Commun. Theor. Phys. 35, 729-734 (2001) | null | null | quant-ph | null | We introduce new kinds of states of quantized radiation fields, which are the
superpositions of negative binomial states. They exhibit remarkable
non-classical properties and reduce to Schr\"odinger cat states in a certain
limit. The algebras involved in the even and odd negative binomial states turn
out to be generally deformed oscillator algebras. It is found that the even and
odd negative binomial states satisfy a same eigenvalue equation with a same
eigenvalue and they can be viewed as two-photon nonlinear coherent states. Two
methods of generating such states are proposed.
| [
{
"version": "v1",
"created": "Sat, 23 Oct 1999 14:00:11 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Wang",
"Xiao-Guang",
""
],
[
"Fu",
"Hong-Chen",
""
]
] |
quant-ph/9910099 | Michael Nielsen | Guifre Vidal, Daniel Jonathan and M. A. Nielsen | Approximate transformations and robust manipulation of bipartite pure
state entanglement | 11 pages, 4 figures | Phys. Rev. A 62, 012304 (2000) | 10.1103/PhysRevA.62.012304 | null | quant-ph | null | We analyze approximate transformations of pure entangled quantum states by
local operations and classical communication, finding explicit conversion
strategies which optimize the fidelity of transformation. These results allow
us to determine the most faithful teleportation strategy via an initially
shared partially entangled pure state. They also show that procedures for
entanglement manipulation such as entanglement catalysis [Jonathan and Plenio,
Phys. Rev. Lett. 83, 3566 (1999)] are robust against perturbation of the states
involved, and motivate the notion of non-local fidelity, which quantifies the
difference in the entangled properties of two quantum states.
| [
{
"version": "v1",
"created": "Sat, 23 Oct 1999 22:39:25 GMT"
},
{
"version": "v2",
"created": "Tue, 26 Oct 1999 01:20:02 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Vidal",
"Guifre",
""
],
[
"Jonathan",
"Daniel",
""
],
[
"Nielsen",
"M. A.",
""
]
] |
quant-ph/9910100 | Hirotaka Sasakura | H. Sasakura and S. Muto | Quantum gates using two-electron states of triple quantum dot | 4 pages(Latex2e), 5 pictures(5 ps-file) | null | null | null | quant-ph | null | Quantum computation using electron spins in three coupled dot with different
size is proposed. By using the energy selectivity of both photon assisted
tunneling and spin rotation of electrons, logic gates are realized by static
and rotational magnetic field and resonant optical pulses. Possibility of
increasing the number of quantum bits using the energy selectivity is also
discussed.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 05:10:44 GMT"
},
{
"version": "v2",
"created": "Tue, 26 Oct 1999 01:15:45 GMT"
},
{
"version": "v3",
"created": "Wed, 27 Oct 1999 02:23:53 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sasakura",
"H.",
""
],
[
"Muto",
"S.",
""
]
] |
quant-ph/9910101 | S. Seshadri | S. Seshadri (1), S. Lakshmibala (2) and V. Balakrishnan (2) ((1) The
Institute of Mathematical Sciences, Chennai, India, (2) Indian Institute of
Technology - Madras, Chennai, India) | Control of Wave Packet Revivals Using Geometric Phases | 11 pages | null | 10.1023/A:1026488815731 | null | quant-ph chao-dyn nlin.CD | null | Wave packets in a system governed by a Hamiltonian with a generic nonlinear
spectrum typically exhibit both full and fractional revivals. It is shown that
the latter can be eliminated by inducing suitable geometric phases in the
states, by varying the parameters in the Hamiltonian cyclically with a period
T. Further, with the introduction of this natural time step T, the occurrence
of near revivals can be mapped onto that of Poincar\'{e} recurrences in an
irrational rotation map of the circle. The distinctive recurrence time
statistics of the latter can thus serve as a clear signature of the dynamics of
wave packet revivals.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 10:40:46 GMT"
}
] | 2015-06-26T00:00:00 | [
[
"Seshadri",
"S.",
""
],
[
"Lakshmibala",
"S.",
""
],
[
"Balakrishnan",
"V.",
""
]
] |
quant-ph/9910102 | S. Seshadri | S. Seshadri (1), S. Lakshmibala (2) and V. Balakrishnan (2) ((1) The
Institute of Mathematical Sciences, Chennai, India, (2) Indian Institute of
Technology - Madras, Chennai, India) | Quantum revivals, geometric phases and circle map recurrences | 9 pages | Phys. Lett. A 256 (1999) 15-19 | 10.1016/S0375-9601(99)00213-3 | null | quant-ph chao-dyn nlin.CD | null | Revivals of the coherent states of a deformed, adiabatically and cyclically
varying oscillator Hamiltonian are examined. The revival time distribution is
exactly that of Poincar\'{e} recurrences for a rotation map: only three
distinct revival times can occur, with specified weights. A link is thus
established between quantum revivals and recurrences in a coarse-grained
discrete-time dynamical system.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 10:20:34 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Seshadri",
"S.",
""
],
[
"Lakshmibala",
"S.",
""
],
[
"Balakrishnan",
"V.",
""
]
] |
quant-ph/9910103 | S. Arun Kumar | R.R. Puri, S. Arun Kumar, and R.K. Bullough | Stroboscopic theory of atomic statistics in the micromaser | 19 pages, 15 included figures, RevTeX | null | null | null | quant-ph | null | We study the statistics of the atoms emerging from the cavity of a micromaser
in a dynamical, discrete-time `stroboscopic' description which takes into
account the measurements made, in general, with imperfect efficiencies, on the
states of the outcoming atoms. Inverted atoms enter stochastically, in general,
with a binomial distribution in discrete time; but we also consider the
continuous-time limit of this input statistics which is Poissonian. We envisage
two alternative experimental procedures: one of these is to consider a fixed
number N of atoms pumped into the cavity and subsequently leaving it to undergo
state detection; the other is to consider input of the excited atoms and their
subsequent detection and collection in a fixed time t. We consider, in
particular, the steady state behaviors achieved in the two limits, N ->
infinity and t -> infinity, as well as the approaches to these two limits.
Although these limits are the same for the state of the cavity field, they are
not the same, in general, for the observable outcoming atom statistics. We
evaluate, in particular, Mandel's Q-parameters $Q_{e}$ $(Q_{g})$ for outcoming
atoms detected in their excited states (ground states), for both N -> infinity
and t -> infinity, as functions of $N_{ex} = RT_{c}$: R is the mean rate of
entry for the incoming atoms and $T_c$ is the cavity damping time. The behavior
of these atomic Q-parameters is compared with that parameter for the cavity
field.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 19:29:53 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Puri",
"R. R.",
""
],
[
"Kumar",
"S. Arun",
""
],
[
"Bullough",
"R. K.",
""
]
] |
quant-ph/9910104 | Ali Mostafazadeh | Ali Mostafazadeh | Perturbative Calculation of the Adiabatic Geometric Phase and Particle
in a Well with Moving Walls | Plain Latex, accepted for publication in J. Phys. A: Math. Gen | J.Phys.A32:8325-8340,1999 | 10.1088/0305-4470/32/47/311 | null | quant-ph hep-th | null | We use the Rayleigh-Schr\"odinger perturbation theory to calculate the
corrections to the adiabatic geometric phase due to a perturbation of the
Hamiltonian. We show that these corrections are at least of second order in the
perturbation parameter. As an application of our general results we address the
problem of the adiabatic geometric phase for a one-dimensional particle which
is confined to an infinite square well with moving walls.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 13:22:16 GMT"
}
] | 2008-11-26T00:00:00 | [
[
"Mostafazadeh",
"Ali",
""
]
] |
quant-ph/9910105 | M. Patra | M. Patra and C. W. J. Beenakker | Propagation of squeezed radiation through amplifying or absorbing random
media | 8 pages, 4 figures | Phys. Rev. A 61, 63805 (2000) | 10.1103/PhysRevA.61.063805 | null | quant-ph cond-mat.mes-hall | null | We analyse how nonclassical features of squeezed radiation (in particular the
sub-Poissonian noise) are degraded when it is transmitted through an amplifying
or absorbing medium with randomly located scattering centra. Both the cases of
direct photodetection and of homodyne detection are considered. Explicit
results are obtained for the dependence of the Fano factor (the ratio of the
noise power and the mean current) on the degree of squeezing of the incident
state, on the length and the mean free path of the medium, the temperature, and
on the absorption or amplification rate.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 14:44:09 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Patra",
"M.",
""
],
[
"Beenakker",
"C. W. J.",
""
]
] |
quant-ph/9910106 | Norbert Luetkenhaus | Miloslav Dusek, Mika Jahma, and Norbert L\"utkenhaus | Unambiguous state discrimination in quantum cryptography with weak
coherent states | 10 pages, 6 figures, updated version with added discussion of
beamsplitting attack | Physical Review A, Vol. 62, 022306 (2000). | 10.1103/PhysRevA.62.022306 | null | quant-ph | null | The use of linearly independent signal states in realistic implementations of
quantum key distribution (QKD) enables an eavesdropper to perform unambiguous
state discrimination. We explore quantitatively the limits for secure QKD
imposed by this fact taking into account that the receiver can monitor to some
extend the photon number statistics of the signals even with todays standard
detection schemes. We compare our attack to the beamsplitting attack and show
that security against beamsplitting attack does not necessarily imply security
against the attack considered here.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 16:53:22 GMT"
},
{
"version": "v2",
"created": "Thu, 27 Apr 2000 06:57:18 GMT"
}
] | 2009-10-31T00:00:00 | [
[
"Dusek",
"Miloslav",
""
],
[
"Jahma",
"Mika",
""
],
[
"Lütkenhaus",
"Norbert",
""
]
] |
quant-ph/9910107 | Subhash Kak | Subhash Kak | On Rotating a Qubit | 5 pages; has one more section and more references | Information Sciences, vol. 128, pp. 149-154, 2000. | null | null | quant-ph | null | The state function of a quantum object is undetermined with respect to its
phase. This indeterminacy does not matter if it is global, but what if the
components of the state have unknown relative phases? Can useful computations
be performed in spite of this local indeterminacy? We consider this question in
relation to the problem of the rotation of a qubit and examine its broader
implications for quantum computing.
| [
{
"version": "v1",
"created": "Mon, 25 Oct 1999 21:44:44 GMT"
},
{
"version": "v2",
"created": "Mon, 1 Nov 1999 22:25:18 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Kak",
"Subhash",
""
]
] |
quant-ph/9910108 | Hitoshi Sakai | K. Sugiyama | Quantum probability from a geometrical interpretation of a wave function | 3 pages | null | null | KS-9913 | quant-ph | null | The probabilistic prediction of quantum theory is mystery. I solved the
mystery by a geometrical interpretation of a wave function. This suggests the
unification between quantum theory and the theory of relativity. This suggests
Many-Worlds Interpretation is true, too.
| [
{
"version": "v1",
"created": "Tue, 26 Oct 1999 14:49:17 GMT"
},
{
"version": "v2",
"created": "Sun, 31 Oct 1999 22:29:15 GMT"
},
{
"version": "v3",
"created": "Thu, 4 Nov 1999 13:33:22 GMT"
},
{
"version": "v4",
"created": "Sun, 21 Nov 1999 05:24:59 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Sugiyama",
"K.",
""
]
] |
quant-ph/9910109 | Igor V. Volovich | I.Ya. Aref'eva and I.V. Volovich | The Large Time Behaviour in Quantum Field Theory and Quantum Chaos | 15 pages, latex | Canadian Math.Soc.Conf.Proc. 29 (2000) 15-27 | null | null | quant-ph cond-mat.stat-mech hep-ph math-ph math.MP | null | An exact general formula for the matrix elements of the evolution operator in
quantum theory is established. The formul ("ABC-formula") has the form
<U(t)>=exp(At+B+C(t)). The constants A and B and the decreasing function C(t)
are computed in perturbation theory. The ABC-formula is valid for a general
class of Hamiltonians used in statistical physics and quantum field theory. The
formula includes the higher order corrections to the well known
Weisskopf-Wigner approximation and to the stochastic (van Hove) limit which are
widely used in considerations of problems of radiation, decay, quantum
decoherence, derivation of master and kinetic equations etc. The function C(t)
admits an interpretation as an analogue of the autocorrelation function
describing quantum chaos for the quantum baker's map.
| [
{
"version": "v1",
"created": "Tue, 26 Oct 1999 13:42:56 GMT"
}
] | 2007-05-23T00:00:00 | [
[
"Aref'eva",
"I. Ya.",
""
],
[
"Volovich",
"I. V.",
""
]
] |
Subsets and Splits