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arXiv · 1601.03643

Intertwined Rashba, Dirac and Weyl Fermions in Hexagonal Hyperferroelectrics

Domenico Di Sante·Paolo Barone·Alessandro Stroppa·Kevin F. Garrity·David Vanderbilt·Silvia Picozzi
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Abstract

By means of density functional theory based calculations, we study the role of spin-orbit coupling in the new family of ABC hyperferroelectrics [Phys. Rev. Lett. 112, 127601 (2014)]. We unveil an extremely rich physics strongly linked to ferroelectric properties, ranging from the electric control of bulk Rashba effect to the existence of a three dimensional topological insulator phase, with concomitant topological surface states even in the ultrathin film limit. Moreover, we predict that the topological transition, as induced by alloying, is followed by a Weyl semi-metal phase of finite concentration extension, which is robust against disorder, putting forward hyperferroelectrics as promising candidates for spin-orbitronic applications.

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Domenico Di Sante, Paolo Barone, Alessandro Stroppa, Kevin F. Garrity, David Vanderbilt, Silvia Picozzi. 2016-01-14. Intertwined Rashba, Dirac and Weyl Fermions in Hexagonal Hyperferroelectrics. https://doi.org/10.1103/physrevlett.117.076401

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