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 ×e2/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.
@article{arxiv.1512.03237,
title = {Quantized one-dimensional edge channels with strong spin-orbit coupling in 3D topological insulators},
author = {Christoph Kastl and Paul Seifert and Xiaoyue He and Kehui Wu and Yongqing Li and Alexander Holleitner},
journal= {arXiv preprint arXiv:1512.03237},
year = {2015}
}