2016/08/31 by Ruihua Fan, Pengfei Zhang, Huitao Shen +1 · 1 citation
Physics and Astronomy · #cond-mat.quant-gas #cond-mat.dis-nn #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1016/j.scib.2017.04.011
published as Science Bulletin, 62 (10), 707-711 (2017) · 6 pages, 3 figures, published version
arxiv created 2017/05/11 · arxiv updated 2017/05/12
In this paper we first compute the out-of-time-order correlators (OTOC) for both a phenomenological model and a random-field XXZ model in the many-body localized phase. We show that the OTOC decreases in power law in a many-body localized system at the scrambling time. We also find that the OTOC can also be used to distinguish a many-body localized phase from an Anderson localized phase, while a normal correlator cannot. Furthermore, we prove an exact theorem that relates the growth of the second Rényi entropy in the quench dynamics to the decay of the OTOC in equilibrium. This theorem works for a generic quantum system. We discuss various implications of this theorem.