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arXiv · quant-ph/0604018

Quantum Reversibility and Echoes in Interacting Systems

Cyril Petitjean·Philippe Jacquod
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Abstract

In Echo experiments, imperfect time-reversal operations are performed on a subset of the total number of degrees of freedom. To capture the physics of these experiments, we introduce a partial fidelity, the Boltzmann echo, where only part of the system's degrees of freedom can be time-reversed. We present a semiclassical calculation of the Boltzmann echo. We show that, as the time-reversal operation is performed more and more accurately, the decay rate of the Boltzmann echo saturates at a value given by the decoherence rate of the controlled degrees of freedom due to their coupling to uncontrolled ones. We connect these results with NMR spin echo experiments.

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Cyril Petitjean, Philippe Jacquod. 2006-04-04. Quantum Reversibility and Echoes in Interacting Systems. https://doi.org/10.1103/physrevlett.97.124103

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