Bulk-Edge correspondence for two-dimensional Floquet topological insulators

Friday, 28 July, 2017

Published in: 

arXiv:1707.09212

Floquet topological insulators describe independent electrons on a lattice driven out of equilibrium by a time-periodic Hamiltonian, beyond the usual adiabatic approximation. In dimension two such systems are characterized by integer-valued topological indices associated to the unitary propagator, alternatively in the bulk or at the edge of a sample. In this paper we give a new definition of the bulk and edge indices not relying on translation invariance and show that they are equal. In particular weak disorder and defects are intrinsically taken into account. Besides this approach naturally provides a physical interpretation of the indices.

Author(s): 

Gian Michele Graf
Clément Tauber