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arXiv · 2410.00439

Spin-mechanical thermal machines

Mohamed Hatifi·Anshuman Nayak·Jason Twamley
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Abstract

We introduce a method to construct a quantum battery and a quantum Otto heat engine using a Nitrogen-Vacancy (NV) center spin coupled to a mechanical oscillator in a highly detuned regime. By precisely controlling the NV spin, we enable efficient energy exchange despite significant detuning, challenging conventional assumptions. This leads to a robust mechanical quantum battery and a cooling scheme driving the oscillator toward its ground state. Leveraging this, we implement a quantum Otto engine that produces mechanical work at maximum efficiency without decoupling from the hot bath, paving the way for practical quantum thermal machines.

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Mohamed Hatifi, Anshuman Nayak, Jason Twamley. 2024-10-01. Spin-mechanical thermal machines. https://doi.org/10.1103/mgjh-rws9

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