arXiv:1411.0946 · Physical Review A

Collapse and revival of quantum coherence for a harmonic oscillator interacting with a classical fluctuating environment

Jacopo Trapani, Matteo Bina, Sabrina Maniscalco, Matteo G. A. Paris

Published Feb 17, 2015• 35 citations

Abstract

We address the dynamics of nonclassicality for a quantum system interacting with a noisy fluctuating environment described by a classical stochastic field. As a paradigmatic example, we consider a harmonic oscillator initially prepared in a maximally nonclassical state, e.g., a Fock number state or a Schr\"odinger-cat-like state, and then coupled to either a resonant or a nonresonant external field. Stochastic modeling allows us to describe the decoherence dynamics without resorting to approximated quantum master equations and to introduce non-Markovian effects in a controlled way. A detailed comparison among different nonclassicality criteria and a thorough analysis of the decoherence time reveal a rich phenomenology whose main features may be summarized as follows: (i) Classical memory effects increase the survival time of quantum coherence and (ii) a detuning between the natural frequency of the system and the central frequency of the classical field induces revivals of quantum coherence.

DOI: 10.1103/physreva.91.022113

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