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arXiv · 2108.08371

Proximity-induced spin-polarized magnetocaloric effect in transition metal dichalcogenides

Abstract

We explore proximity-induced magnetocaloric effect (MCE) on transition metal dichalcogenides, focusing on a two-dimensional (2D) MoTe$_2$ monolayer deposited on a ferromagnetic semiconductor EuO substrate connected to a heat source. We model this heterostructure using a tight-binding model, incorporating exchange and Rashba fields induced by proximity to EuO, and including temperature through Fermi statistics. The MCE is induced on the 2D MoTe$_2$ layer due to the EuO substrate, revealing large spin-polarized entropy changes for energies out of the band gap of the MoTe$_2$-EuO system. By gating the chemical potential, the MCE can be tuned to produce heating for spin up and cooling for spin down across the $K$ and $K'$ valley splitting in the valence band, whereas either heats or cools for both spins in the conduction band. The Rashba field enhances the MCE in the valence zone while decreasing it in the conduction bands. The exchange field-induced MCE could be useful to produce tunable spin-polarized thermal responses in magnetic proximitized 2D materials.

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BibTeXRIS

Natalia Cortés, Francisco J. Peña, Oscar Negrete, Patricio Vargas. 2021-08-18. Proximity-induced spin-polarized magnetocaloric effect in transition metal dichalcogenides. https://doi.org/10.1103/physrevb.105.014443

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