Magnonic Thermal Machines

• DOI: 10.48550/arxiv.2404.08153
• Publication Date: 2024-01-01
• Authors: Vidal-Silva, N.; Peña, Francisco J.; Troncoso, Roberto E.; Vargas, Patricio
• Keywords: Condensed Matter - Strongly Correlated Electrons; Condensed Matter - Mesoscale and Nanoscale Physics; Strongly Correlated Electrons (cond-mat.str-el); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); FOS: Physical sciences

10 pages. Supplemental material included<br/>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.<br/>