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arXiv · 1504.05232

Enhanced electron correlations at the SrxCa1-xVO3 surface

J. Laverock·J. Kuyyalil·B. Chen·R. P. Singh·G. Balakrishnan·B. Karlin·J. C Woicik·K. E. Smith
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Abstract

We report hard x-ray photoemission spectroscopy measurements of the electronic structure of the prototypical correlated oxide SrxCa1-xVO3. By comparing spectra recorded at different excitation energies, we show that 2.2 keV photoelectrons contain a substantial surface component, whereas 4.2 keV photoelectrons originate essentially from the bulk of the sample. Bulk-sensitive measurements of the O 2p valence band are found to be in good agreement with ab initio calculations of the electronic structure, with some modest adjustments to the orbital-dependent photoionization cross sections. The evolution of the O 2p electronic structure as a function of the Sr content is dominated by A-site hybridization. Near the Fermi level, the correlated V 3d Hubbard bands are found to evolve in both binding energy and spectral weight as a function of distance from the vacuum interface, revealing higher correlation at the surface than in the bulk.

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J. Laverock, J. Kuyyalil, B. Chen, R. P. Singh, G. Balakrishnan, B. Karlin, J. C Woicik, K. E. Smith. 2015-04-20. Enhanced electron correlations at the SrxCa1-xVO3 surface. https://doi.org/10.1103/physrevb.91.165123

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