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Action scales for quantum decoherence and their relation to structures in phase space

Daniel Alonso·S. Brouard·Jose P. Palao·R. Sala Mayato
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Abstract

A characteristic action $ΔS$ is defined whose magnitude determines some properties of the expectation value of a general quantum displacement operator. These properties are related to the capability of a given environmental `monitoring' system to induce decoherence in quantum systems coupled to it. We show that the scale for effective decoherence is given by $ΔS\approx\hbar$. We relate this characteristic action with a complementary quantity, $ΔZ$, and analyse their connection with the main features of the pattern of structures developed by the environmental state in different phase space representations. The relevance of the $ΔS$-action scale is illustrated using both a model quantum system solved numerically and a set of model quantum systems for which analytical expressions for the time-averaged expectation value of the displacement operator are obtained explicitly.

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Daniel Alonso, S. Brouard, Jose P. Palao, R. Sala Mayato. 2004-03-02. Action scales for quantum decoherence and their relation to structures in phase space. https://doi.org/10.1103/physreva.69.052111

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