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arXiv · 2208.06578

Bath engineering enhanced quantum critical engines

Revathy B. S.·Victor Mukherjee·Uma Divakaran
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Abstract

Driving a quantum system across quantum critical points leads to non-adiabatic excitations in the system. This in turn may adversely affect the functioning of a quantum machine which uses a quantum critical substance as its working medium. Here we propose a bath-engineered quantum engine (BEQE), in which we use the Kibble--Zurek mechanism and critical scaling laws to formulate a protocol for enhancing the performance of finite-time quantum engines operating close to quantum phase transitions. In the case of free fermionic systems, BEQE enables finite-time engines to outperform engines operating in the presence of shortcuts to adiabaticity, and even infinite-time engines under suitable conditions, thus showing the remarkable advantages offered by this technique. Open questions remain regarding the use of BEQE based on non-integrable models.

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Revathy B. S., Victor Mukherjee, Uma Divakaran. 2022-08-13. Bath engineering enhanced quantum critical engines. https://doi.org/10.3390/e24101458

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