Possible experimental realization of a basic Z2 topological semimetal in GaGeTe

DOI: 10.1063/1.5124563

Authors: Erik Haubold (IFW Dresden) , Alexander Fedorov (HZB Helmholtz-Zentrum Berlin für Materialien und Energie) , Florian Pielnhofer (Max Planck Institute for Solid State Research; Universität Regensburg) , Igor P. Rusinov (Tomsk State University; St. Petersburg State University) , Tatiana V. Menshchikova (Tomsk State University) , Viola Duppel (Max Planck Institute for Solid State Research) , Daniel Friedrich (Universität Regensburg) , Richard Weihrich (Universität Augsburg) , Arno Pfitzner (Universität Regensburg) , Alexander Zeugner (IFW Dresden; TU Dresden) , Anna Isaeva (IFW Dresden; TU Dresden) , Setti Thirupathaiah (IFW Dresden) , Yevhen Kushnirenko (IFW Dresden) , Emile Rienks (IFW Dresden; TU Dresden) , Timur Kim (Diamond Light Source) , Evgueni V. Chulkov (Tomsk State University; St. Petersburg State University; Donostia International Physics Center; University of the Basque Country (UPV/EHU)) , Bernd Büchner (IFW Dresden; TU Dresden) , Sergey Borisenko (Leibniz Institute for Solid State and Materials Research Dresden)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Apl Materials , VOL 7

State: Published (Approved)
Published: December 2019
Diamond Proposal Number(s): 18586

Abstract: We report experimental and theoretical evidence that GaGeTe is a basic Z2 topological semimetal with three types of charge carriers: bulk-originated electrons and holes as well as surface state electrons. This electronic situation is qualitatively similar to the classic 3D topological insulator Bi2Se3, but important differences account for an unprecedented transport scenario in GaGeTe. High-resolution angle-resolved photoemission spectroscopy combined with advanced band structure calculations show a small indirect energy gap caused by a peculiar band inversion at the T-point of the Brillouin zone in GaGeTe. An energy overlap of the valence and conduction bands brings both electron and holelike carriers to the Fermi level, while the momentum gap between the corresponding dispersions remains finite. We argue that peculiarities of the electronic spectrum of GaGeTe have a fundamental importance for the physics of topological matter and may boost the material’s application potential.

Subject Areas: Materials, Physics


Instruments: I05-ARPES

Other Facilities: BESSY II

Added On: 13/12/2019 08:21

Discipline Tags:

Quantum Materials Physics Hard condensed matter - structures Materials Science

Technical Tags:

Spectroscopy Angle Resolved Photoemission Spectroscopy (ARPES)