Structure of surface electronic states in strained mercury telluride

• Published in: New Journal of Physics
• Main Authors: Kibis, Oleg, Kyriienko, O., Shelykh, Ivan
• Other Authors: Raunvísindastofnun (HÍ), Science Institute (UI), Verkfræði- og náttúruvísindasvið (HÍ), School of Engineering and Natural Sciences (UI), Háskóli Íslands, University of Iceland
• Format: Article in Journal/Newspaper
• Language: English
• Published: IOP Publishing 2019
• Subjects: Strained HgTe; Surface states; Topological insulator; Grannfræði; Ástand efnis; Iceland
• Online Access: https://hdl.handle.net/20.500.11815/1773; https://doi.org/10.1088/1367-2630/ab1406

Publisher's version (útgefin grein) We present the theory describing the various surface electronic states arisen from the mixing of conduction and valence bands in a strained mercury telluride (HgTe) bulk material. We demonstrate that the strain-induced band gap in the Brillouin zone center of HgTe results in the surface states of two different kinds. Surface states of the first kind exist in the small region of electron wave vectors near the center of the Brillouin zone and have the Dirac linear electron dispersion characteristic for topological states. The surface states of the second kind exist only far from the center of the Brillouin zone and have the parabolic dispersion for large wave vectors. The structure of these surface electronic states is studied both analytically and numerically in the broad range of their parameters, aiming to develop its systematic understanding for the relevant model Hamiltonian. The results bring attention to the rich surface physics relevant for topological systems. The work was partially supported by Horizon2020 RISE project COEXAN, Russian Foundation for Basic Research (project 17-02-00053), Rannis project 163082-051, Ministry of Education and Science of Russian Federation (projects 3.457 3.2017/6.7, 3.261 4.2017/4.6, 14.Y26.31.0015), and the Government of the Russian Federation through the ITMO Fellowship and Professorship Program. OVK and OK thank the University of Iceland for hospitality. Peer Reviewed