arXiv:0907.1590 · Journal of Physics A Mathematical and Theoretical

Thermodynamics and fluctuation theorems for a strongly coupled open quantum system: an exactly solvable case

Michele Campisi, Peter Talkner, Peter Hänggi

Published Sep 11, 2009• 52 citations

Abstract

We illustrate recent results concerning the validity of the work fluctuation theorem in open quantum systems [M. Campisi, P. Talkner, and P. Hänggi, Phys. Rev. Lett. {\bf 102}, 210401 (2009)], by applying them to a solvable model of an open quantum system. The central role played by the thermodynamic partition function of the open quantum system, -- a two level fluctuator with a strong quantum nondemolition coupling to a harmonic oscillator --, is elucidated. The corresponding quantum Hamiltonian of mean force is evaluated explicitly. We study the thermodynamic entropy and the corresponding specific heat of this open system as a function of temperature and coupling strength and show that both may assume negative values at nonzero low temperatures.

DOI: 10.1088/1751-8113/42/39/392002

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