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arXiv · 1901.02276

Zeeman-type spin splitting in non-magnetic three-dimensional compounds: Materials prediction and electrical control

Abstract

Despite its potential for device application, the non-magnetic Zeeman effect has only been predicted and observed in two-dimensional compounds. We demonstrate that non-centrosymmetric three-dimensional compounds can also exhibit a Zeeman-type spin splitting, allowing the splitting control by changing the growth direction of slabs formed by these compounds. We determine the required conditions for this effect: $i$) non-centrosymmetric including polar and non-polar point groups, $ii$) valence band maximum or conduction band minimum in a generic $k$-point, i.e., non-time-reversal-invariant momentum, and $iii$) zero magnetic moment. Using these conditions as filters, we perform a material screening to systematically search for these systems in the aflow-ICSD database. We find 20 material candidates featuring the Zeeman-type effect. We also found that the spin-splitting in confined systems can be controlled by an external electric field, which in turns can induce a metal-insulator transition. We believe that the Zeeman-type effect in three-dimensional compounds can potentially be used for spin-filtering devices.

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Carlos Mera Acosta, Adalberto Fazzio, Gustavo M. Dalpian. 2019-01-08. Zeeman-type spin splitting in non-magnetic three-dimensional compounds: Materials prediction and electrical control. https://doi.org/10.1038/s41535-019-0182-z

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