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Dissipative quantum systems modeled by a two level reservoir coupling

A. O. Caldeira·A. H. Castro Neto·T. Oliveira de Carvalho
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Abstract

The coupling between a quantum dynamical system and a two-level system reservoir is analysed within the framework of the Feynman-Vernon theory. We stress the differences between this new reservoir and the well-known bath of oscillators and show that, in order to obtain the Langevin equation for the system of interest in the high temperature regime, we have to choose a spectral distribution function $J(ω)$ which is finite for $ω=0$.

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A. O. Caldeira, A. H. Castro Neto, T. Oliveira de Carvalho. 1993-08-31. Dissipative quantum systems modeled by a two level reservoir coupling. https://doi.org/10.1103/physrevb.48.13974

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