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arXiv · 2005.12382

Persistent many-body quantum echoes

Lennart Dabelow·Peter Reimann
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Abstract

We consider quantum many-body systems evolving under a time-independent Hamiltonian $H$ from a nonequilibrium initial state at time $t=0$ towards a close-to-equilibrium state at time $t=\tau$. Subsequently, this state is slightly perturbed and finally propagated for another time period $\tau$ under the inverted Hamiltonian $-H$. The entire procedure may also be viewed as an imperfect time inversion or "echo dynamics". We unravel a remarkable persistence of such dynamics with respect to the observable deviations of the time-dependent expectation values from the equilibrium expectation value: For most perturbations, the deviations in the final state are essentially independent of the inversion time point $\tau$. Our quantitative analytical predictions compare very well with exact numerical results.

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BibTeXRIS

Lennart Dabelow, Peter Reimann. 2020-05-25. Persistent many-body quantum echoes. https://doi.org/10.1103/physrevresearch.2.023216

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