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arXiv · 1512.03237

Quantized one-dimensional edge channels with strong spin-orbit coupling in 3D topological insulators

Christoph Kastl·Paul Seifert·Xiaoyue He·Kehui Wu·Yongqing Li·Alexander Holleitner
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Abstract

A strong coupling between the electron spin and its motion is one of the prerequisites of spin-based data storage and electronics. A major obstacle is to find spin-orbit coupled materials where the electron spin can be probed and manipulated on macroscopic length scales, for instance across the gate channel of a spin-transistor. Here, we report on millimeter-scale edge channels with a conductance quantized at a single quantum 1 $\times$ $e^2/h$ at zero magnetic field. The quantum transport is found at the lateral edges of three-dimensional topological insulators made of bismuth chalcogenides. The data are explained by a lateral, one-dimensional quantum confinement of non-topological surface states with a strong Rashba spin-orbit coupling. This edge transport can be switched on and off by an electrostatic field-effect. Our results are fundamentally different from an edge transport in quantum spin Hall insulators and quantum anomalous Hall insula-tors.

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Christoph Kastl, Paul Seifert, Xiaoyue He, Kehui Wu, Yongqing Li, Alexander Holleitner. 2015-12-10. Quantized one-dimensional edge channels with strong spin-orbit coupling in 3D topological insulators. https://arxiv.org/abs/1512.03237

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