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arXiv · 1812.07598

Quantum Scrambling and State Dependence of the Butterfly Velocity

Xizhi Han·Sean A. Hartnoll
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Abstract

Operator growth in spatially local quantum many-body systems defines a scrambling velocity. We prove that this scrambling velocity bounds the state dependence of the out-of-time-ordered correlator in local lattice models. We verify this bound in simulations of the thermal mixed-field Ising spin chain. For scrambling operators, the butterfly velocity shows a crossover from a microscopic high temperature value to a distinct value at temperatures below the energy gap.

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Xizhi Han, Sean A. Hartnoll. 2018-12-18. Quantum Scrambling and State Dependence of the Butterfly Velocity. https://doi.org/10.21468/scipostphys.7.4.045

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