Non-Equilibrium Aspects of Floquet Chern Insulators
Abstract: During the last decade, it has been demonstrated that topological structures in condensed matter systems may be realized under non-equilibrium conditions where external time-dependent perturbations represent a rich and versatile resource that can be used to achieve topological properties. Specifically, periodic driving may give rise to new Hamiltonians with non-trivial topological insulator spectra, known as Floquet topological/Chern insulators (FTIs). However, being driven these systems are far out of equilibrium and have unique non-equilibrium aspects that must be taken into account in any realistic setting.
In this talk, I review some of the highlights of our previous works on non-equilibrium aspects of these systems under closed quench, and open dissipative non-equilibrium protocols where we demonstrate that the system is described by non-thermal steady states. The specific model studied here is a hexagonal lattice such as graphene, under the irradiation of circularly polarized laser fields. I review our theoretical predictions for experimentally measurable quantities including the angle-resolved photoemission spectroscopy (ARPES), and the DC Hall conductance. Finally, in presence of a quench electron-electron interaction and periodic driving the possibility of a superconducting phase transition in a hexagonal lattice at the mean field level is investigated.
Host: Mohammad Hafezi