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arXiv · 1911.05905

Computing characteristic functions of quantum work in phase space

Yixiao Qian·Fei Liu
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Abstract

In phase space, we analytically obtain the characteristic functions (CFs) of a forced harmonic oscillator [Talkner et al., Phys. Rev. E, 75, 050102 (2007)], a time-dependent mass and frequency harmonic oscillator [Deffner and Lutz, Phys. Rev. E, 77, 021128 (2008)], and coupled harmonic oscillators under driving forces in a simple and unified way. For general quantum systems, a numerical method that approximates the CFs to $\hbar^2$ order is proposed. We exemplify the method with a time-dependent frequency harmonic oscillator and a family of quantum systems with time-dependent even power-law potentials.

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Yixiao Qian, Fei Liu. 2019-11-14. Computing characteristic functions of quantum work in phase space. https://doi.org/10.1103/physreve.100.062119

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