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arXiv · 1605.01050

Evolution of a quantum harmonic oscillator coupled to a minimal thermal environment

A. Vidiella-Barranco
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Abstract

In this paper it is studied the influence of a minimal thermal environment on the dynamics of a quantum harmonic oscillator (labelled A), prepared in a coherent state. The environment itself consists of a second oscillator (labelled B), initially in a thermal state. Two types of interaction Hamiltonians are considered, and the time-evolution of the reduced density operator of oscillator A is compared to the one obtained from the usual master equation approach, i.e., assuming that oscillator A is coupled to a large reservoir. An analysis of the linear entropy evolution of oscillator A shows that simplified models may be able to describe important features related to the phenomenon of decoherence.

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A. Vidiella-Barranco. 2016-05-03. Evolution of a quantum harmonic oscillator coupled to a minimal thermal environment. https://doi.org/10.1016/j.physa.2016.04.033

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