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arXiv · 1611.04058

Out-of-Time-Order Correlation in Marginal Many-Body Localized Systems

Kevin Slagle·Zhen Bi·Yi-Zhuang You·Cenke Xu
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Abstract

We show that the out-of-time-order correlation (OTOC) $ \langle W(t)^\dagger V(0)^\dagger W(t)V(0)\rangle$ in many-body localized (MBL) and marginal MBL systems can be efficiently calculated by the spectrum bifurcation renormalization group (SBRG). We find that in marginal MBL systems, the scrambling time $t_\text{scr}$ follows a stretched exponential scaling with the distance $d_{WV}$ between the operators $W$ and $V$: $t_\text{scr}\sim\exp(\sqrt{d_{WV}/l_0})$, which demonstrates Sinai diffusion of quantum information and the enhanced scrambling by the quantum criticality in non-chaotic systems.

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Kevin Slagle, Zhen Bi, Yi-Zhuang You, Cenke Xu. 2017-04-22. Out-of-Time-Order Correlation in Marginal Many-Body Localized Systems. https://doi.org/10.1103/physrevb.95.165136

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