10ILM - Institut Lumière Matière [Villeurbanne] (UMR5306 CNRS Université Claude Bernard Lyon 1 Domaine Scientifique de La Doua Bâtiment Kastler, 10 rue Ada Byron 69622 Villeurbanne CEDEX, Franc - France)
Abstract : Topological crystalline insulators are a type of topological insulators whose topological surface states are protected by a crystal symmetry, thus the surface gap can be tuned by applying strain or an electric field. In this paper we predict by means of ab initio calculations a new phase of Bi which is a topological crystalline insulator characterized by a mirror Chern number n M = −2, but not a Z 2 strong topological insulator. This system presents an exceptional property: at the (001) surface its Dirac cones are pinned at the surface high-symmetry points. As a consequence they are also protected by time-reversal symmetry and can survive against weak disorder even if in-plane mirror symmetry is broken at the surface. Taking advantage of this dual protection, we present a strategy to tune the band-gap based on a topological phase transition unique to this system. Since the spin-texture of these topological surface states reduces the back-scattering in carrier transport, this effective band-engineering is expected to be suitable for electronic and optoelectronic devices with reduced dissipation.
https://hal-univ-lyon1.archives-ouvertes.fr/hal-02290196 Contributor : Depot 3 Lyon 1Connect in order to contact the contributor Submitted on : Thursday, February 4, 2021 - 10:37:11 AM Last modification on : Wednesday, December 22, 2021 - 5:58:01 PM Long-term archiving on: : Wednesday, May 5, 2021 - 6:18:45 PM
F. Munoz, M. G. Vergniory, T. Rauch, J. Henk, E. V. Chulkov, et al.. Topological Crystalline Insulator in a New Bi Semiconducting Phase. Scientific Reports, Nature Publishing Group, 2016, 6, pp.21790. ⟨10.1038/srep21790⟩. ⟨hal-02290196⟩