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arXiv · 1906.10222

Electrical and magnetic properties of thin films of the spin-filter material CrVTiAl

Gregory M. Stephen·Christopher Lane·Gianina Buda·David Graf·Stanislaw Kaprzyk·Bernardo Barbiellini·Arun Bansil·Don Heiman
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Abstract

The spin-filter material CrVTiAl is a promising candidate for producing highly spin-polarized currents at room temperature in a nonmagnetic architecture. Thin films of compensated-ferrimagnetic CrVTiAl have been grown and their electrical and magnetic properties have been studied. The resistivity shows two-channel semiconducting behavior with one disordered gapless channel and a gapped channel with activation energy $ΔE$=~0.1~-~0.2~eV. Magnetoresistance measurements to B~=~35~T provide values for the mobilities of the gapless channel, leading to an order of magnitude difference in the carrier effective masses, which are in reasonable accord with our density-functional-theory based results. The density of states and electronic band structure is computed for permutations of the four sublattices arranged differently along the (111) body diagonal, yielding metallic (Cr-V-Al-Ti), spin-gapless (Cr-V-Ti-Al) and spin-filtering (Cr-Ti-V-Al) phases. Robustness of the spin-gapless phase to substitutional disorder is also considered.

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Gregory M. Stephen, Christopher Lane, Gianina Buda, David Graf, Stanislaw Kaprzyk, Bernardo Barbiellini, Arun Bansil, Don Heiman. 2019-06-24. Electrical and magnetic properties of thin films of the spin-filter material CrVTiAl. https://doi.org/10.1103/physrevb.99.224207

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