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arXiv · 1411.4539

Low-energy V t2g orbital excitations in NdVO3

J. Laverock·B. Chen·A. R. H. Preston·D. Newby Jr.·L. F. J. Piper·L. D. Tung·G. Balakrishnan·P. -A. Glans·J. -H. Guo·K. E. Smith
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Abstract

The electronic structure of NdVO3, YVO3 has been investigated as a function of sample temperature using resonant inelastic soft x-ray scattering at the V L3-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 t2g states. Moreover, this feature exhibits a strong sample temperature dependence, reaching maximum intensity in the orbitally-ordered phase of NdVO3, 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.

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J. Laverock, B. Chen, A. R. H. Preston, D. Newby Jr., L. F. J. Piper, L. D. Tung, G. Balakrishnan, P. -A. Glans, J. -H. Guo, K. E. Smith. 2014-11-17. Low-energy V t2g orbital excitations in NdVO3. https://doi.org/10.1088/0953-8984%2F26%2F45%2F455603

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