11 research outputs found
Novel Orbital Ordering induced by Anisotropic Stress in a Manganite Thin Film
We performed resonant and nonresonant x-ray diffraction studies of a
Nd0.5Sr0.5MnO3 thin film that exhibits a clear first-order transition. Lattice
parameters vary drastically at the metal-insulator transition at 170K (=T_MI),
and superlattice reflections appear below 140K (=T_CO). The electronic
structure between T_MI and T_CO is identified as A-type antiferromagnetic with
the d_{x2-y2} ferroorbital ordering. Below T_CO, a new type of antiferroorbital
ordering emerges. The accommodation of the large lattice distortion at the
first-order phase transition and the appearance of the novel orbital ordering
are brought about by the anisotropy in the substrate, a new parameter for the
phase control.Comment: 4pages, 4figure
Polarization-analyzed resonant inelastic x-ray scattering of the orbital excitations in KCuF3
We report a Cu K-edge resonant inelastic x-ray scattering (RIXS) study of
orbital excitations in KCuF3 . By performing the polarization analysis of the
scattered photons, we disclose that the excitation between the eg orbitals and
the excitations from t2g to eg exhibit distinct polarization dependence. The
polarization dependence of the respective excitations is interpreted based on a
phenomenological consideration of the symmetry of the RIXS process that yields
a necessary condition for observing the excitations. In addition, we show that
the orbital excitations are dispersionless within our experimental resolution.Comment: 5 pages, 3 figure