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arXiv · 1504.02901

Work measurement in an optomechanical quantum heat engine

Ying Dong·Keye Zhang·Francesco Bariani·Pierre Meystre
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Abstract

We analyze theoretically the measurement of the mean output work and its fluctuations in a recently proposed optomechanical quantum heat engine [K. Zhang {\it et al.} Phys. Rev. Lett. {\bf112}, 150602 (2014)]. After showing that this work can be evaluated by a continuous measurements of the intracavity photon number we discuss both dispersive and absorptive measurement schemes and analyze their back-action effects on the efficiency of the engine. Both measurements are found to reduce the efficiency of the engine, but their back-action is both qualitatively and quantitatively different. For dispersive measurements the efficiency decreases as a result of the mixing of photonic and phononic excitations, while for absorptive measurements, its reduction results from photon losses due to the interaction with the quantum probe.

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Ying Dong, Keye Zhang, Francesco Bariani, Pierre Meystre. 2015-04-11. Work measurement in an optomechanical quantum heat engine. https://doi.org/10.1103/physreva.92.033854

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