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arXiv · 2108.05378

Unidirectional magneto-transport of linearly dispersing topological edge states

Zhanning Wang·Pankaj Bhalla·Mark Edmonds·Michael S. Fuhrer·Dimitrie Culcer
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Abstract

Quantum spin-Hall edges are envisaged as next-generation transistors, yet they exhibit dissipationless transport only over short distances. Here we show that in a diffusive sample, where charge puddles with odd spin cause back-scattering, a magnetic field drastically increases the mean free path and drives the system into the ballistic regime with a Landauer-Buttiker conductance. A strong non-linear non-reciprocal current emerges in the diffusive regime with opposite signs on each edge, and vanishes in the ballistic limit. We discuss its detection in state-of-the-art experiments.

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Zhanning Wang, Pankaj Bhalla, Mark Edmonds, Michael S. Fuhrer, Dimitrie Culcer. 2021-08-11. Unidirectional magneto-transport of linearly dispersing topological edge states. https://doi.org/10.1103/physrevb.104.l081406

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