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arXiv · 1903.02651

Information Scrambling and Loschmidt Echo

Bin Yan·Lukasz Cincio·Wojciech H. Zurek
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Abstract

We demonstrate analytically and verify numerically that the out-of-time order correlator is given by the thermal average of Loschmidt echo signals. This provides a direct link between the out-of-time-order correlator -- a recently suggested measure of information scrambling in quantum chaotic systems -- and the Loschmidt echo, a well-appreciated familiar diagnostic that captures the dynamical aspect of chaotic behavior in the time domain, and is accessible to experimental studies.

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Bin Yan, Lukasz Cincio, Wojciech H. Zurek. 2020-04-24. Information Scrambling and Loschmidt Echo. https://doi.org/10.1103/physrevlett.124.160603

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