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arXiv · 2109.06946

Inverse magnetocaloric effect in synthetic antiferromagnets

D. M. Polishchuk·M. Persson·M. M. Kulyk·E. Holmgren·G. Pasquale·A. Ullah·R. Skomski·V. Korenivski
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Abstract

The magnetocaloric effect in exchange-coupled synthetic-antiferromagnet multilayers is investigated experimentally and theoretically. We observe a temperature-controlled inversion of the effect, where the entropy increases on switching the individual ferromagnetic layers from anti-parallel to parallel alignment near their Curie point. Using a microscopic analytical model as well as numerical atomistic-spin simulations of the system, we explain the observed effect as due to the interplay between the intra- and inter-layer exchange interactions, which either add up or counteract to effectively modulate the Curie temperature of the dilute ferromagnetic layers. The proposed method of designing tunable, strongly magneto-caloric materials should be of interest for such applications as heat-assisted spintronics and magnetic refrigeration.

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D. M. Polishchuk, M. Persson, M. M. Kulyk, E. Holmgren, G. Pasquale, A. Ullah, R. Skomski, V. Korenivski. 2021-09-14. Inverse magnetocaloric effect in synthetic antiferromagnets. https://arxiv.org/abs/2109.06946

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