Dissipative preparation of many-body Floquet Chern insulators

Abstract

Considering coupling to a micro-structured bath as a relaxation mechanism in a periodically driven dissipative Haldane model, we establish that the system may be tuned to a stroboscopic topological steady state at all finite temperatures. The amplitude and frequency of the periodic drive is so chosen that the Floquet Hamiltonian describing the Haldane model at stroboscopic instants of time in the unitary situation is topologically non-trivial. We establish that in the stroboscopic steady state, the system reaches a thermal state of the Floquet Hamiltonian at a controlled temperature. Further, it is observed that even with a coupling to a quasi-local bath, remarkably a Chern insulator can indeed be prepared in a Chern non-trivial pure steady state which is expected to exhibit a stroboscopic bulkboundary correspondence. Using the non-uniqueness of the macroscopic bulk electric polarisation of a Chern insulator in its topological phase, we propose a generalised Chern invariant that reflects the topology of out-of-equilibrium many-body stroboscopic states of the Haldane model even in a dissipative ambience. The generalised topology of dynamical Chern insulators being dependent on single-particle correlations, is expected to manifest in experiments probing many-body quantum observables.

Disorder in dissipation-induced topological states: Evidence for a different type of localization transition

“…This stands in line with the usual perception of driving and dissipation as causing decoherence and destroying subtle quantum phenomena. However, this point of view has been challenged by recent works showing how coupling to an environment could be engineered to drive a system towards desired steady states displaying quantum correlations [3][4][5][6][7][8][9], such as nonequilibrium topological states [10][11][12][13][14][15][16][17][18][19][20][21][22][23]. In particular, Refs.…”

Dynamic renormalization group theory for open Floquet systems

“…They have recently gained a lot of interest, because of their fundamentally new properties. or example, periodic drives can be used to generate artificial gauge fields for ultracold atoms [22][23][24][25][26], time crystals in atomic [27], ionic [28] or dissipative [29][30][31][32][33] systems, novel topological states without equilibrium counterparts [26,[34][35][36][37][38][39][40][41][42][43][44][45], driven analogs of many-body localization [46][47][48][49] or Floquet spinor Bose gases [50][51][52].…”