Ferroelectricity driven by Y d0-ness with rehybridization in YMnO3.
We investigated electronic structure of hexagonal multiferroic YMnO3 using the polarization dependent x-ray absorption spectroscopy (XAS) at O K and Mn L(2,3) edges. The spectra exhibit strong polarization dependence at both edges, reflecting anisotropic Mn 3d orbital occupation. Moreover, the O K edge spectra show that Y 4d states are strongly hybridized with O 2p ones, resulting in large anomalies in Born effective charges on off-centering Y and O ions. These results manifest that the Y d(0)-ness with rehybridization is the driving force for the ferroelectricity, and suggest a new approach to understand the multiferroicity in the hexagonal manganites.
Cho
D-Y
DY
CSCMR & School of Physics and Astronomy, Seoul National University, Seoul 151-747, Korea.
Kim
J-Y
JY
Park
B-G
BG
Rho
K-J
KJ
Park
J-H
JH
Noh
H-J
HJ
Kim
B J
BJ
Oh
S-J
SJ
Park
H-M
HM
Ahn
J-S
JS
Ishibashi
H
H
Cheong
S-W
SW
Lee
J H
JH
Murugavel
P
P
Noh
T W
TW
Tanaka
A
A
Jo
T
T