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arXiv · 1506.06705

Heat transport between antiferromagnetic insulators and normal metals

Arne Brataas·Hans Skarsvåg·Erlend G. Tveten·Eirik Løhaugen Fjærbu
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Abstract

Antiferromagnetic insulators can become active spintronics components by controlling and detecting their dynamics via spin currents in adjacent metals. This cross-talk occurs via spin-transfer and spin-pumping, phenomena that have been predicted to be as strong in antiferromagnets as in ferromagnets. Here, we demonstrate that a temperature gradient drives a significant heat flow from magnons in antiferromagnetic insulators to electrons in adjacent normal metals. The same coefficients as in the spin-transfer and spin-pumping processes also determine the thermal conductance. However, in contrast to ferromagnets, the heat is not transferred via a spin Seebeck effect which is absent in antiferromagnetic insulator-normal metal systems. Instead, the heat is transferred via a large staggered spin Seebeck effect.

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Arne Brataas, Hans Skarsvåg, Erlend G. Tveten, Eirik Løhaugen Fjærbu. 2015-06-22. Heat transport between antiferromagnetic insulators and normal metals. https://doi.org/10.1103/physrevb.92.180414

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