Raman spectroscopy of epitaxial topological insulator Bi2Te3 thin films on GaN substrates
Artikel i vetenskaplig tidskrift, 2015

Bi2Te3 has drawn great attention in recent years as both a topological insulator and the best thermoelectric material at room temperature. We report on Raman spectroscopic study on Bi2Te3 thin films with thicknesses of 20-50 nm grown on GaN by molecular beam epitaxy. All the four classical optical phonon modes are clearly revealed for the first time in ex situ Raman for epitaxial Bi2Te3. Unusual and infrared-active vibration modes are also observed and analyzed. In the resonant Raman measurements, abnormal enhancement and suppression of different modes are studied. The interface modes caused by a large density of domain boundaries formed during coalescence of crystal islands with different lattice orientations and the Frohlich electron-phonon interaction are found to play significant roles during the Raman scattering processes.

domain boundaries

electron-phonon interaction

Bi2Te3

Raman spectroscopy

Topological insulator

resonant Raman scattering

Författare

H. Xu

Chinese Academy of Sciences

Y. X. Song

Chinese Academy of Sciences

Q. Gong

Chinese Academy of Sciences

W. W. Pan

Chinese Academy of Sciences

X. Y. Wu

Chinese Academy of Sciences

Shu Min Wang

Chalmers, Mikroteknologi och nanovetenskap (MC2), Fotonik

Modern Physics Letters B

0217-9849 (ISSN)

Vol. 29 15

Ämneskategorier

Nanoteknik

DOI

10.1142/s021798491550075x