Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MA: Fachverband Magnetismus

MA 51: Topological Insulators I (joined session with TT)

MA 51.2: Vortrag

Donnerstag, 23. März 2017, 10:00–10:15, POT 251

2D Topological Insulators: Trends in Chemical Space — •Carlos Mera Acosta^1,2, Christian Carbogno¹, Adalberto Fazzio², Luca M. Ghiringhelli¹, and Matthias Scheffler¹ — ¹Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin — ²Instituto de Física, Universidade de São Paulo, SP, Brazil

2D topological insulators (TI) have attracted considerable scientific interest in recent years [1]. The search for new TIs has often focused on elements with strong spin-orbit coupling (SOC) [2], which can induce the necessary topological transition. In this work, we have computed the topological invariant Z₂ for 200 functionalized honeycomb-lattice systems using our recent Wannier center of charge (WCC) [3] implementation in the FHI-aims electronic structure code. Besides confirming the TI character of well-known materials, e.g., functionalized stanene [1], our study found several other yet unreported TIs. This reveals that also elements with relatively low SOC can form TIs. To analyze the observed trends in chemical space we relate the WCCs to the atomic features of the constituent atoms using a compressed-sensing approach. For this purpose, the LASSO and ℓ₀ minimization of Ref. [4] is extended from learning scalar properties to functions.

This work received funding from The Novel Materials Discovery (NOMAD) Laboratory, a European Centre of Excellence.

[1] Y. Ren, Z. Qiao, and Q. Niu, RPP 79, 6 66501 (2016).

[2] M. Z. Hasan and C. L. Kane, Rev. Mod. Phys. 82, 3045 (2010).

[3] R. Yu, et al., Phys. Rev. B 84, 075119 (2011).

[4] L. M. Ghirighelli, et al., Phys. Rev. Lett. 114, 105503 (2015).