Dispersion of the surface phonons in semiconductor/topological insulator Si/Bi2Te3 heterostructure studied by high resolution Brillouin spectroscopy
Artikel i vetenskaplig tidskrift, 2021

The dynamics and dispersion of surface phonons in heterostructure semiconductor/ topological insulator Si/Bi2Te3 was investigated using high resolution Brillouin light scattering method in the GHz frequency range. Both Rayleigh and Sezawa surface acoustic waves have been observed for wave vectors ranging from 0.006 to 0.023 nm−1. Anomaly in dispersion relations ω(q) for both surface waves were detected for the wave vector q = 0.016 nm−1. The finite element method (FEM) was used to simulate the observed shapes of ω(q) and to find the deformation profiles of surface acoustic waves. We attribute the observed changes to the coupling between low energy electrons and surface phonons. The coupling between helical Dirac states and surface phonons is discussed in the frame of accessible theoretical models.

Topological insulator

Finite Element Method

Surface phonons

Brillouin spectroscopy

Electron phonon coupling

Rayleigh and Sezawa waves

Elastic properties

Författare

A. Trzaskowska

Uniwersytet im. Adama Mickiewicza w Poznaniu

S. Mielcarek

Uniwersytet im. Adama Mickiewicza w Poznaniu

M. Wiesner

Uniwersytet im. Adama Mickiewicza w Poznaniu

Floriana Lombardi

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

B. Mroz

Uniwersytet im. Adama Mickiewicza w Poznaniu

Ultrasonics

0041-624X (ISSN)

Vol. 117 106526

Ämneskategorier

Atom- och molekylfysik och optik

Annan fysik

Den kondenserade materiens fysik

DOI

10.1016/j.ultras.2021.106526

Mer information

Senast uppdaterat

2021-08-26