Topological currents in black phosphorus with broken inversion symmetry

Tony Low; Yongjin Jiang; Francisco Guinea

doi:10.1103/physrevb.92.235447

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arXiv · 1507.06930

Topological currents in black phosphorus with broken inversion symmetry

Tony Low·Yongjin Jiang·Francisco Guinea

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Abstract

We examine the nature of topological currents in black phosphorus when its inversion symmetry is deliberately broken. Here, the conduction and valence band edges are located at the $Γ$ point of the rectangular Brillouin zone, and they exhibit strong anisotropy along its two crystal axes. We will show below that these salient features lead to a linear transverse neutral topological currents, accompanied also by a non-linear transverse charge current at the Fermi surface. These topological currents are maximal when the in-plane electric field is applied along the zigzag crystal axes, but zero along the armchair direction.

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Tony Low, Yongjin Jiang, Francisco Guinea. 2015-07-24. Topological currents in black phosphorus with broken inversion symmetry. https://doi.org/10.1103/physrevb.92.235447

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