Edge states in two-dimensional topological semimetal with non-symmorphic symmetry

TKM Institutsseminar

Vortragender:

Polina Matveeva

Datum:

22.11.2018 14:00

Ort:

Room 10.01, 10th Floor, Bldg. 30.23, KIT Campus South

Zugehörigkeit:

Technische Universität Kaiserslautern

Gastgeber:

Dr. Igor Gornyi

Abstract

Dirac materials have unique transport properties, partly due to the presence of surface states.
A new type of Dirac materials, protected by non-symmorphic symmetries, was recently proposed by Young and Kane [1].
By breaking of time reversal or inversion symmetry one can split the Dirac cones into Weyl nodes.
The latter are characterised by a local Chern numbers that makes them two dimensional analogue of Weyl semimetals.

We find that the formation of the Weyl nodes is accompanied by an emergence of one dimensional surface states, similar to Fermi arcs in Weyl semimetals and edge states in two dimensional graphene. We explore those states for quasi-one dimensional non-symmorphic ribbon. The type and strength of applied deformation controls Weyl nodes and consequently the characteristics of the edge states that emerge.
The sensitivity of edge states to the external deformations makes non-symmorphic materials to be potentially useful as a new type of electro-mechanical sensors.

[1] Steve M. Young and Charles L. Kane, "Dirac semimetals in two dimensions", Phys. Rev. Lett. 115, 126803 (2015)