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arXiv · 2508.14183

Relativistic Quantum Thermal Machine: Harnessing Relativistic Effects to Surpass Carnot Efficiency

Tanmoy Pandit·Pritam Chattopadhyay·Kaustav Chatterjee·Varinder Singh
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Abstract

We investigate a three-level maser quantum thermal machine in which the system-reservoir interaction is modeled via Unruh-DeWitt type coupling, with one or both reservoirs undergoing relativistic motion relative to the working medium. Motion induces Doppler reshaping of the reservoir spectra, modifying energy-exchange rates and enabling operation beyond the Carnot efficiency at finite power. We numerically analyze families of efficiency-power curves and extract the analytic form of a generalized Carnot bound, which recovers the Carnot limit. In addition, Doppler reshaping alters the boundaries between heat-engine and refrigerator operation, making it possible to extract positive work even in the absence of a temperature gradient. These findings establish relativistic motion as a genuine thermodynamic resource.

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Tanmoy Pandit, Pritam Chattopadhyay, Kaustav Chatterjee, Varinder Singh. 2025-08-19. Relativistic Quantum Thermal Machine: Harnessing Relativistic Effects to Surpass Carnot Efficiency. https://arxiv.org/abs/2508.14183

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