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arXiv · 1504.07975

Dynamics of two externally driven coupled quantum oscillators interacting with separate baths based on path integrals

Illarion Dorofeyev
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Abstract

The paper deals with the problem of dynamics of externally driven open quantum systems. Using the path integral methods we found an analytical expression for time-dependent density matrix of two externally driven coupled quantum oscillators interacting with different baths of oscillators. It is shown that at the zeroing of external forces the density matrix becomes identical to the previously obtained one for freely developing coupled oscillators. Mean values of observables are computed by using the Hermitian part of the matrix. All elements of the covariance matrix composed by coordinates and momenta of two driven coupled oscillators are calculated. The time-dependent mean values, dispersions and covariances of coordinates of coupled oscillators at given external forces are numerically studied. It is shown that the larger the coupling constant the larger is the disturbances of the second oscillator due to external action on the first oscillator. Coupled dynamics of forced oscillators at relatively large coupling constant is demonstrated at different thermodynamic conditions.

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Illarion Dorofeyev. 2015-04-29. Dynamics of two externally driven coupled quantum oscillators interacting with separate baths based on path integrals. https://doi.org/10.1016/j.physa.2015.11.008

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