Low-energy V t2g orbital excitations in NdVO3.

ABSTRACT

The electronic structure of NdVO(3) and YVO(3) has been investigated as a function of sample temperature using resonant inelastic soft x-ray scattering at the V L(3)-edge. Most of the observed spectral features are in good agreement with an atomic crystal-field multiplet model. However, a low energy feature is observed at ∼ 0.4 eV that cannot be explained by crystal-field arguments. The resonant behaviour of this feature establishes it as due to excitations of the V t(2g) states. Moreover, this feature exhibits a strong sample temperature dependence, reaching maximum intensity in the orbitally-ordered phase of NdVO(3), before becoming suppressed at low temperatures. This behaviour indicates that the origin of this feature is a collective orbital excitation, i.e. the bi-orbiton.