Nontrivial topological valence bands of common diamond and zinc-blende semiconductors

DOI: 10.1103/PhysRevMaterials.3.064203

Authors: Tomáš Rauch (Friedrich-Schiller-University Jena) , Victor A. Rogalev (Universität Würzburg) , Maximilian Bauernfeind (Universität Würzburg) , Julian Maklar (Universität Würzburg) , Felix Reis (Universität Würzburg) , Florian Adler (Universität Würzburg) , Simon Moser (Universität Würzburg) , Johannes Weis (Universität Würzburg) , Tien-lin Lee (Diamond Light Source) , Pardeep K. Thakur (Diamond Light Source) , Jörg Schäfer (Universität Würzburg) , Ralph Claessen (Universität Würzburg) , Jürgen Henk (Martin Luther University Halle-Wittenberg) , Ingrid Mertig (Martin Luther University Halle-Wittenberg; Max Planck Institute for Microstructure Physics)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Physical Review Materials , VOL 3 , PAGES 064203

State: Published (Approved)
Published: June 2019
Diamond Proposal Number(s): 19512

Abstract: The diamond and zinc-blende semiconductors are well-known and have been widely studied for decades. Yet, their electronic structure still surprises with unexpected topological properties of the valence bands. In this joint theoretical and experimental investigation, we demonstrate for the benchmark compounds InSb and GaAs that the electronic structure features topological surface states below the Fermi energy. Our parity analysis shows that the spin-orbit split-off band near the valence band maximum exhibits a strong topologically nontrivial behavior characterized by the Z 2 invariants ( 1 ; 000 ) . The nontrivial character is a consequence of the nonzero spin-orbit coupling and is imposed by the chosen constituents, in contrast to the conventional topological phase transition mechanism which relies on tuning parameters in the system Hamiltonian. Ab initio-based tight-binding calculations resolve topological surface states in the occupied electronic structure of InSb and GaAs, further confirmed experimentally by soft x-ray angle-resolved photoemission from both materials. Our findings are valid for all other materials whose valence bands are adiabatically linked to those of InSb, i.e., many diamond and zinc-blende semiconductors, as well as other related materials, such as half-Heusler compounds.

Journal Keywords: Symmetry protected topological states; Topological insulators; Topological phases of matter; Semiconductor compounds; Semiconductors; Topological materials; Angle-resolved photoemission spectroscopy

Subject Areas: Materials, Physics


Instruments: I09-Surface and Interface Structural Analysis