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arXiv · 2504.16440

Spin-dependent Transport Studies of Fe/Mo$_x$Cr$_{1-x}$S$_2$/Fe Magnetic Tunnel Junction

Abstract

Using Density functional theory and non-equilibrium Green's function formalism, spin dependent electron transport in Fe/Mo$_x$Cr$_{1-x}$S$_2$/Fe magnetic tunnel junction is studied. Spin transport for different thicknesses (1, 3, 5, and 7 layers) of the spacer MoS2 and for two different surface orientations of the Fe electrode, the Fe(001) and Fe(111) surface and with substitutional doping of 3d transition metal Cr at Mo site in MoS2 is investigated. The electronic structure of the heterostructure shows the presence of metal-induced states in the semiconducting MoS2 at the Fe/MoS2/Fe interface. The I-V characteristics of the junctions for the monolayer and three layer MoS2 spacer show linear behaviour due to the metallic nature of the junction. The tunnelling nature of the junction is observed for the thicker junctions with five-layer and seven layer spacers. With the introduction of magnetic impurity Cr, the tunnelling magnetoresistance for 7-layer junction is reduced. The Cr-defect states are observed below the conduction band, and the Cr-doped devices are stable up to a bias of 0.5V. Spin-transport through close-packed Fe(111) surface as electrode show low GMR value.

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BibTeXRIS

Aloka Ranjan Sahoo, Sharat Chandra. 2026-01-05. Spin-dependent Transport Studies of Fe/Mo$_x$Cr$_{1-x}$S$_2$/Fe Magnetic Tunnel Junction. https://doi.org/10.1016/j.jmmm.2025.173652

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