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Two-level masers as heat-to-work converters.

ABSTRACT: Heat engines, which cyclically transform heat into work, are ubiquitous in technology. Lasers and masers may be viewed as heat engines that rely on population inversion or coherence in the active medium. Here we put forward an unconventional paradigm of a remarkably simple and robust electromagnetic heat-powered engine that bears basic differences to any known maser or laser: The proposed device makes use of only one Raman transition and does not rely on population inversion or coherence in its two-level working medium. Nor does it require any coherent driving. The engine can be powered by the ambient temperature difference between the sky and the ground surface. Its autonomous character and "free" power source make this engine conceptually and technologically enticing.

SUBMITTER: Ghosh A

PROVIDER: S-EPMC6176601 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Two-level masers as heat-to-work converters.

Ghosh Arnab A Gelbwaser-Klimovsky David D Niedenzu Wolfgang W Lvovsky Alexander I AI Mazets Igor I Scully Marlan O MO Kurizki Gershon G

Proceedings of the National Academy of Sciences of the United States of America 20180918 40

Heat engines, which cyclically transform heat into work, are ubiquitous in technology. Lasers and masers may be viewed as heat engines that rely on population inversion or coherence in the active medium. Here we put forward an unconventional paradigm of a remarkably simple and robust electromagnetic heat-powered engine that bears basic differences to any known maser or laser: The proposed device makes use of only one Raman transition and does not rely on population inversion or coherence in its ...[more]

PMID: 30228114

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