Observation of infrared-active modes in Raman scattering from topological insulator nanoplates.
Two infrared (IR)-active vibrational modes, observed at 93 and 113 cm(-1) in Raman scattering, are evidence of an inversion symmetry breakdown in thin (~10 nm) nanoplates of topological insulator Bi(2)Te(3) as-grown on SiO(2). Both Raman and IR modes are preserved after typical device fabrication processes. In nanoplates transferred to another SiO(2) substrate via contact printing, however, the IR modes are absent, and the Raman spectra are similar to those from bulk samples. The differences between as-grown and transferred nanoplates may result from nanoplate-substrate interactions.
Department of Physics, University of Northern Iowa, Cedar Falls, IA 50614-0150, USA.
Rui
R
He
Zhenhua
Z
Wang
Richard L J
RL
Qiu
Conor
C
Delaney
Ben
B
Beck
T E
TE
Kidd
C C
CC
Chancey
Xuan P A
XP
Gao