Observation of time-reversal-protected single-dirac-cone topological-insulator states in Bi2Te3 and Sb2Te3.
We show that the strongly spin-orbit coupled materials Bi2Te3 and Sb2Te3 and their derivatives belong to the Z2 topological-insulator class. Using a combination of first-principles theoretical calculations and photoemission spectroscopy, we directly show that Bi2Te3 is a large spin-orbit-induced indirect bulk band gap (delta approximately 150 meV) semiconductor whose surface is characterized by a single topological spin-Dirac cone. The electronic structure of self-doped Sb2Te3 exhibits similar Z2 topological properties. We demonstrate that the dynamics of spin-Dirac fermions can be controlled through systematic Mn doping, making these materials classes potentially suitable for topological device applications.
Hsieh
D
D
Joseph Henry Laboratories of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Xia
Y
Y
Qian
D
D
Wray
L
L
Meier
F
F
Dil
J H
JH
Osterwalder
J
J
Patthey
L
L
Fedorov
A V
AV
Lin
H
H
Bansil
A
A
Grauer
D
D
Hor
Y S
YS
Cava
R J
RJ
Hasan
M Z
MZ