Title: Detecting topological transitions in two dimensions by Hamiltonian evolution,
Abstract: We show that the evolution of two-component particles governed by a
two-dimensional spin-orbit lattice Hamiltonian can reveal transitions between
topological phases. A kink in the mean width of the particle distribution
signals the closing of the band gap, a prerequisite for a quantum phase
transition between topological phases. Furthermore, for realistic and
experimentally motivated Hamiltonians the density profile in topologically
non-trivial phases displays characteristic rings in the vicinity of the origin
that are absent in trivial phases. The results are expected to have immediate
application to systems of ultracold atoms and photonic lattices.