Interlayer Spin Transport in 2D Material Heterostructures with Arbitrary Epitaxies: A Computational Design from Bulk Properties

Recently, magnetic tunnel junctions (MTJs) demonstrated in two-dimensional materials (2DMs) are promising for spin transport applications. The facile formation of 2DM-based junctions without epitaxial constraints of bulk MTJs demand quantitative transport descriptions to rapidly prescreen systems. Here we present a model based on the physical properties of bulk constituents, circumventing the computational burden of full quantum transport. Mechanisms governing transport in these heterostructures are determined from the electronic and complex band structures of individual 2DMs in their bulk form using density functional theory. We analyze the dependence of tunneling and magnetoresistance on various features such as effective tunneling rates, van der Waals gap, and binding energy. Importantly, our model can tackle systems with arbitrary epitaxies, which are usually intractable for first principles calculations. We discuss the cases where heterostructures are formed by either magnetic channels or magnetic leads, with emphasis given to Fe-dihalides which show tunneling magnetoresistance values of up to 10,000%. The good agreement between this model and full quantum transport calculations in heterostructures signals promising potential for the accelerated data-driven screening of 2DM candidates for use in spintronic applications.