Title: Odd-triplet superconductivity in single-level quantum dots,
Abstract: We study the interplay of spin and charge coherence in a single-level quantum
dot. A tunnel coupling to a superconducting lead induces superconducting
correlations in the dot. With full spin symmetry retained, only even-singlet
superconducting correlations are generated. An applied magnetic field or
attached ferromagnetic leads partially or fully reduce the spin symmetry, and
odd-triplet superconducting correlations are generated as well. For
single-level quantum dots, no other superconducting correlations are possible.
We analyze, with the help of a diagrammatic real-time technique, the interplay
of spin symmetry and superconductivity and its signatures in electronic
transport, in particular current and shot noise.