# Nanoscale heat engine beyond the Carnot limit.

@article{Ronagel2014NanoscaleHE, title={Nanoscale heat engine beyond the Carnot limit.}, author={J. Ro{\ss}nagel and Obinna Abah and Ferdinand Schmidt-Kaler and Kilian Singer and Eric Lutz}, journal={Physical review letters}, year={2014}, volume={112 3}, pages={ 030602 } }

We consider a quantum Otto cycle for a time-dependent harmonic oscillator coupled to a squeezed thermal reservoir. We show that the efficiency at maximum power increases with the degree of squeezing, surpassing the standard Carnot limit and approaching unity exponentially for large squeezing parameters. We further propose an experimental scheme to implement such a model system by using a single trapped ion in a linear Paul trap with special geometry. Our analytical investigations are supported…

## 351 Citations

Two-level quantum Otto heat engine operating with unit efficiency far from the quasi-static regime under a squeezed reservoir

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Recent theoretical and experimental studies in quantum heat engines show that, in the quasi-static regime, it is possible to have higher efficiency than the limit imposed by Carnot, provided that…

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A many-body heat engine at criticality

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We show that a quantum Otto cycle in which the medium, an interacting ultracold gas, is driven between a superfluid and an insulating phase can outperform similar single particle cycles. The presence…

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The optimal efficiency at the unified trade-off optimization criterion representing a compromise between energy benefits and losses for a quantum Otto heat engine is systematically investigated.

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Trapped ions in linear Paul traps have been established as a powerful platform for performing experiments in quantum optics, quantum computing, quantum simulation, quantum control, and more recently…

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We consider a thermodynamic machine in which the working fluid is a quantized harmonic oscillator that is controlled on timescales that are much faster than the oscillator period. We find that…

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A heat engine operating in the one-shot finite-size regime, where systems composed of a small number of quantum particles interact with hot and cold baths and are restricted to one-shot measurements,…

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