Activating many-body localization in solids by driving

Coupling to phonons prevents many body localization (MBL) from occurring in disordered solids even when the disorder is strong. This is because phonons mediate non-local interaction which weakly breaks local conservation laws characteristic for the MBL phase. Nevertheless, I will show that decay of local conservation laws can be compensated when the system is driven out of equilibrium. We propose to detect the fingerprints of an underlying MBL phase by measuring the variation of local temperatures in the resulting steady state.

The concrete example I will consider is a one-dimensional disordered spin-chain which is weakly coupled to a phonon bath and weakly irradiated by white light. The irradiation has weak effects in the ergodic phase. However, if the system is in the MBL phase irradiation induces strong temperature variations. Temperature variation can be used similar to an order parameter to detect MBL phases, the phase transition, an MBL correlation length and even the critical exponents. Finite coupling strengths broaden the transition into a crossover, potentially containing information on the Griffiths effects. I will address this using tensor network and variational ansatz approaches.


Z. Lenarcic, E. Altman, and A. Rosch, arXiv:1806.04772 (2018)