Momentum dependence of orbital excitations in Mott-insulating titanates.
High-resolution resonant inelastic x-ray scattering has been used to determine the momentum dependence of orbital excitations in Mott-insulating LaTiO(3) and YTiO(3) over a wide range of the Brillouin zone. The data are compared to calculations in the framework of lattice-driven and superexchange-driven orbital ordering models. A superexchange model in which the experimentally observed modes are attributed to two-orbiton excitations yields the best description of the data.
Ulrich
C
C
Max-Planck-Institut für Festkörperforschung, D-70569 Stuttgart, Germany.
Ament
L J P
LJ
Ghiringhelli
G
G
Braicovich
L
L
Moretti Sala
M
M
Pezzotta
N
N
Schmitt
T
T
Khaliullin
G
G
van den Brink
J
J
Roth
H
H
Lorenz
T
T
Keimer
B
B