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arXiv · 2404.08153

Magnonic Thermal Machines

N. Vidal-Silva·Francisco J. Peña·Roberto E. Troncoso·Patricio Vargas
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Abstract

We propose a magnon-based thermal machine in two-dimensional (2D) magnetic insulators. The thermodynamical cycles are engineered by exposing a magnon spin system to thermal baths at different temperatures and tuning the Dzyaloshinskii-Moriya (DM) interaction. We find for the Otto cycle that a thermal gas of magnons converts a fraction of heat into energy in the form of work, where the efficiency is maximized for specific values of DM, reaching the corresponding Carnot efficiency. We witness a positive to negative net work transition during the cycle that marks the onset of a refrigerator-like behavior. The work produced by the magnonic heat engine enhances the magnon chemical potential. The last enables a spin accumulation that might result in the pumping of spin currents at the interfaces of metal-magnet heterostructures. Our work opens new possibilities for the efficient leverage of conventional two-dimensional magnets.

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N. Vidal-Silva, Francisco J. Peña, Roberto E. Troncoso, Patricio Vargas. 2024-04-11. Magnonic Thermal Machines. https://doi.org/10.1103/physrevresearch.6.033164

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