Theme 3 colloquium: 'In silico discovery of novel topological materials' (Lecture)
- Tuesday 21 June 2022Add to my calendar
- from 16:00
Prof. Oleg V. Yazyev (Institute of Physics, École Polytechnique Fédérale de Lausanne)
In my talk, I will focus on our recent efforts directed towards the search of novel topological materials. A large number of diverse topological electronic phases that can be realized in materials have been predicted recently. We have developed a high-throughput computational screening methodology for identifying materials hosting various topological phases among known materials. The entire dataset of results obtained using this high-throughput search is now publicly available via the Materials Cloud platform . Several predictions resulting from this search that have been successfully confirmed by experiments. A new Z2 topological insulator was theoretically predicted and experimentally confirmed in the β-phase of quasi-one-dimensional bismuth iodide Bi4I4 . The electronic structure of β-Bi4I4, characterized by Z2 invariants (1;110), is in proximity of both the weak TI phase (0;001) and the trivial insulator phase (0;000). We further predicted robust type-II Weyl semimetal phase in transition metal diphosphides MoP2 and WP2 characterized by very large momentum-space separation between Weyl points of opposite chirality . Recent experiments on WP2 revealed record magnitudes of magnetoresistance combined with very high conductivity and residual resistivity ratio , and many other extraordinary properties. I will discuss in detail the physical mechanism underlying magnetotransport in WP2 as well as in other trivial and topological semimetals .
 G. Autès, Q. S. Wu, N. Mounet, and O. V. Yazyev, “TopoMat: a database of high-throughput first-principles calculations of topological materials”, https://www.materialscloud.org/discover/topomat
 G. Autès et al., Nature Mater. 15, 154 (2016).
 G. Autès, D. Gresch, M. Troyer, A. A. Soluyanov and O. V. Yazyev, Phys. Rev. Lett. 117, 066402 (2016).
 N. Kumar et al., Nature Commun. 8, 1642 (2017).
 S. N. Zhang, Q. S. Wu, Y. Liu and O. V. Yazyev, Phys. Rev. B 99, 035142 (2019).
Andrey Bagrov and Nadine Hauptmann