Dimensionality-controlled insulator-metal transition and correlated metallic state in 5d transition metal oxides Sr n+1Ir nO3n+1 (n=1, 2, and infinity).
We investigated the electronic structures of the 5d Ruddlesden-Popper series Sr n+1Ir nO3n+1 (n=1, 2, and infinity) using optical spectroscopy and first-principles calculations. As 5d orbitals are spatially more extended than 3d or 4d orbitals, it has been widely accepted that correlation effects are minimal in 5d compounds. However, we observed a Mott insulator-metal transition with a change of bandwidth as we increased n. In addition, the artificially synthesized perovskite SrIrO3 showed a very large mass enhancement of about 6, indicating that it was in a correlated metallic state.
Moon
S J
SJ
ReCOE & FPRD, Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
Jin
H
H
Kim
K W
KW
Choi
W S
WS
Lee
Y S
YS
Yu
J
J
Cao
G
G
Sumi
A
A
Funakubo
H
H
Bernhard
C
C
Noh
T W
TW