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arXiv · 1903.08551

Open quantum systems in Heisenberg picture

Fardin Kheirandish
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Abstract

In the framework of the Heisenberg picture, an alternative derivation of the reduced density matrix of a driven dissipative quantum harmonic oscillator as the prototype of an open quantum system is investigated. The reduced density matrix for different initial states of the combined system is obtained from a general formula, and different limiting cases are studied. Exact expressions for the corresponding characteristic function in quantum thermodynamics and Wigner quasi distribution function are found. A possible generalization based on the Magnus expansion of the evolution operator is presented.

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Fardin Kheirandish. 2019-03-20. Open quantum systems in Heisenberg picture. https://arxiv.org/abs/1903.08551

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