Persistent many-body quantum echoes

• URL: http://arxiv.org/abs/2005.12382v1
• Date: Mon, 25 May 2020 20:28:30 GMT
• Title: Persistent many-body quantum echoes
• Authors: Lennart Dabelow and Peter Reimann
• Abstract summary: We consider quantum many-body systems evolving under a time-independent Hamiltonian $H$. We unravel a remarkable persistence of such dynamics with respect to the observable deviations of the time-dependent expectation values.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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