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arXiv · 2311.18026

Ferroelectric Semimetals with $\alpha$-Bi/SnSe van der Waals heterostructures and its Topological Currents

D. J. P. de Sousa·Seungjun Lee·Qiangsheng Lu·Rob G. Moore·Matthew Brahlek·J-. P. Wang·Guang Bian·Tony Low
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Abstract

We show that proximity effects can be utilized to engineer van der Waals heterostructures (vd- WHs) displaying spin-ferroelectricity locking, where ferroelectricity and spin states are confined to different layers, but are correlated by means of proximity effects. Our findings are supported by first principles calculations in $\alpha$-Bi/SnSe bilayers. We show that such systems support ferroelectrically switchable non-linear anomalous Hall effect originating from large Berry curvature dipoles as well as direct and inverse spin Hall effects with giant bulk spin-charge interconversion efficiencies. The giant efficiencies are consequences of the proximity-induced semimetallic nature of low energy electron states, which are shown to behave as two-dimensional pseudo-Weyl fermions by means of symmetry analysis, first principles calculations as well as direct angle-resolved photoemission spectroscopy measurements.

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D. J. P. de Sousa, Seungjun Lee, Qiangsheng Lu, Rob G. Moore, Matthew Brahlek, J-. P. Wang, Guang Bian, Tony Low. 2023-11-29. Ferroelectric Semimetals with $\alpha$-Bi/SnSe van der Waals heterostructures and its Topological Currents. https://arxiv.org/abs/2311.18026

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