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arXiv · 1903.05004

Structural and electronic properties of the spin-filter material CrVTiAl with disorder

Gregory M. Stephen·Gianina Buda·Michelle E. Jamer·Christopher Lane·Stanislaw Kaprzyk·Bernardo Barbiellini·David Graf·Laura H. Lewis·Arun Bansil·Don Heiman
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Abstract

The effects of chemical disorder on the transport properties of the spin-filter material CrVTiAl are investigated experimentally and theoretically. Synchrotron X-ray diffraction experiments on bulk CrVTiAl and the associated Rietveld analysis indicate that the crystal structure consists primarily of a mixture of a partially ordered B2 phase, a fully disordered A2 phase and a small component of an ordered L2\textsubscript{1} or Y phase. High temperature resistivity measurements confirm the existence of a band gap. First-principles, all-electron, self-consistent electronic structure computations show that the chemically disordered A2 and B2 phases are metallic, while the spin-filter properties of the ideal Y-type phase are preserved in the presence of L2\textsubscript{1} disorder. The Hall coefficient is found to decrease with increasing temperature, similar to the measured increase in the conductivity, indicating the presence of thermally activated semiconductor-like carriers.

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Gregory M. Stephen, Gianina Buda, Michelle E. Jamer, Christopher Lane, Stanislaw Kaprzyk, Bernardo Barbiellini, David Graf, Laura H. Lewis, Arun Bansil, Don Heiman. 2019-03-12. Structural and electronic properties of the spin-filter material CrVTiAl with disorder. https://doi.org/10.1063/1.5079749

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