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arXiv · 1412.0898

Nonequilibrium fluctuations in quantum heat engines: Theory, example, and possible solid state experiments

Michele Campisi·Jukka Pekola·Rosario Fazio
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Abstract

We study the stochastic energetic exchanges in quantum heat engines. Due to microreversibility, these obey a fluctuation relation, called the heat engine fluctuation relation, which implies the Carnot bound: no machine can have an efficiency larger than Carnot's efficiency. The stochastic thermodynamics of a quantum heat engine (including the joint statistics of heat and work and the statistics of efficiency) is illustrated by means of an optimal two-qubit heat engine, where each qubit is coupled to a thermal bath and a two-qubit gate determines energy exchanges between the two qubits. We discuss possible solid state implementations with Cooper pair boxes and flux qubits, quantum gate operations, and fast calorimetric on-chip measurements of single stochastic events.

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Michele Campisi, Jukka Pekola, Rosario Fazio. 2014-12-02. Nonequilibrium fluctuations in quantum heat engines: Theory, example, and possible solid state experiments. https://doi.org/10.1088/1367-2630/17/3/035012

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