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Survival of quantum effects for observables after decoherence

G. P. Berman·A. R. Bishop·F. Borgonovi·D. A. R. Dalvit
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Abstract

When a quantum nonlinear system is linearly coupled to an infinite bath of harmonic oscillators, quantum coherence of the system is lost on a decoherence time-scale $τ_D$. Nevertheless, quantum effects for observables may still survive environment-induced decoherence, and be observed for times much larger than the decoherence time-scale. In particular, we show that the Ehrenfest time, which characterizes a departure of quantum dynamics for observables from the corresponding classical dynamics, can be observed for a quasi-classical nonlinear oscillator for times $τ\ggτ_D$. We discuss this observation in relation to recent experiments on quantum nonlinear systems in the quasi-classical region of parameters.

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G. P. Berman, A. R. Bishop, F. Borgonovi, D. A. R. Dalvit. 2004-01-08. Survival of quantum effects for observables after decoherence. https://doi.org/10.1103/physreva.69.062110

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