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DOE OSTI · 1726166

Information Scrambling and Loschmidt Echo

Cincio, Lukasz·Yan, Bin·Zurek, Wojciech Hubert
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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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0-dimensional systems75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYChaos & nonlinear dynamicsExact diagonalizationMathematicsQuantum chaosQuantum chaotic systemsQuantum statistical mechanicsQuantum thermodynamics

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

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