CONDENSED MATTER

Semiclassical scattering by edge imperfections in topological insulators in a magnetic field

A. Sh. Dotdaev^a, Ya. I. Rodionov^b, A. V. Rozhkov^b, P. D. Grigoriev<sup>c

a</sup> National University of Science and Technology MISIS, Moscow, 119049 Russia
^b Institute for Theoretical and Applied Electrodynamics, Russian Academy of Sciences, Moscow, 125412 Russia
^c Landau Institute for Theoretical Physics, Russian Acedemy of Sciences, Moscow, 117940 Russia

Abstract: We study the scattering of edge states of 2D topological insulator in the uniform external magnetic field due to edge imperfections, common in realistic 2D topological insulator samples. The external magnetic field breaks time-reversal symmetry, opening the possibility of the scattering of otherwise topologically protected fermionic edge states. The scattering happens to be always an over-barrier event, irrespective of the shape of the edge deformation and magnitude of the magnetic field. We use the advanced Pokrovsky–Khalatnikov semiclassical approach, which allows us to obtain analytically both the main exponential and pre-exponential factors of the scattering amplitude for wide classes of analytic deformation profiles.

Received: 28.08.2024
Revised: 19.09.2024
Accepted: 21.09.2024

DOI: 10.31857/S0370274X24110086

 English version: Journal of Experimental and Theoretical Physics Letters, 2024, 120:9, 675–686