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

Jyotipratim Ray Chaudhuri·Bimalendu Deb·Gautam Gangopadhyay Deb Shankar Ray
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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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Jyotipratim Ray Chaudhuri, Bimalendu Deb, Gautam Gangopadhyay Deb Shankar Ray. 1999-02-15. Quantum theory of dissipation of a harmonic oscillator coupled to a nonequilibrium bath; Wigner-Weisskopf decay and physical spectra. https://doi.org/10.1088/0953-4075%2F31%2F17%2F011

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