Quantum theory of dissipation of a harmonic oscillator coupled to a nonequilibrium bath: Wigner-Weisskopf decay and physical spectra

Chaudhuri, J R, Deb, B, Shankar, Ray D

Published Jan 1, 1998• 7 citations

Abstract

We extend the quantum theory of dissipation in the context of system-reservoir model, where the reservoir in question is kept in a nonequilibrium condition. Based on a systematic separation of time scales involved in the dynamics, appropriate generalizations of the fluctuation-dissipation and Einstein's relations have been pointed out. We show that the Wigner-Weisskopf decay of the system mode results in a rate constant which depending on the relaxation of nonequilibrium bath is dynamically modified. We also calculate the time-dependent spectra of a cavity mode with a suitable gain when the cavity is kept in contact with a nonequilibrium bath.

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