Speaker
Ms
Giulia Manzoni
(University of Trieste, Trieste, Italy)
Description
ZrTe5 has recently stimulated in-depth investigations aimed at clarifying its ground state electronic properties. In fact, the material has been proposed to be a 3D Dirac semimetal [1], a prototype of weak topological insulator [2] or a topological insulator in proximity of a topological phase transition [3].
Here we report a comprehensive experimental and theoretical study of both its electronic and structural properties, revealing that the bulk stoichiometric ZrTe5 is a strong topological insulator (STI).
By means of angle-resolved photoelectron spectroscopy, we resolve at the top of the valence band both a surface and a bulk state. The band dispersions are well captured by ab-initio fully relativistic calculations for the STI case, for the specific interlayer distance value measured in our x-ray diffraction study. Finally, scanning tunneling spectroscopy shows that the sample surface is metallic, with no band gap in the density of states, thus confirming the strong topological character of ZrTe5.
[1] Qiang Li et al., Nature Physics (2016), doi:10.1038/nphys3648.
[2] R. Wu et al., arXiv:1601.07056 (2015)
[3] H. Weng et al., Physical review X 4, 011002 (2014).
Primary author
Ms
Giulia Manzoni
(University of Trieste, Trieste, Italy)
Co-authors
Dr
Alberto Crepaldi
(Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland)
Mr
Andrea Sterzi
(University of Trieste, Trieste, Italy)
Dr
Federico Cilento
(Elettra - Sincrotrone Trieste, Trieste, Italy)
Prof.
Fulvio Parmigiani
(University of Trieste, Trieste, Italy)
Dr
Helmuth Berger
(Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland)
Dr
Luca Gragnaniello
(University of Konstanz, Konstanz, Germany)
Dr
Michele Zacchigna
(C.N.R. - I.O.M., Trieste, Italy)
Prof.
Oleg Yazyev
(Institute of Theoretical Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland)
