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Universality of quantum Brownian motion

Eric Lutz·Hans A. Weidenmueller
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Abstract

Are Markovian master equations for quantum Brownian motion independent of model assumptions used in the derivation and, thus, universal? With the aim of answering this question, we use a random band-matrix model for the system-bath interaction to derive Markovian master equations for the time evolution of one-dimensional quantum systems weakly coupled to a heat bath. We study in detail two simple systems, the harmonic oscillator and the two-level system. Our results are in complete agreement with those of earlier models, like the Caldeira-Legget model and, in the large-band limit, with the Agarwal equations (both with and without rotating-wave approximation). This proves the universality of these master equations.

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Eric Lutz, Hans A. Weidenmueller. 1998-11-02. Universality of quantum Brownian motion. https://doi.org/10.1016/s0378-4371(99)00022-9

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