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Surface vs. bulk Coulomb correlations in photoemission spectra of perovskites

A. Liebsch
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Abstract

Recent photoemission spectra of the perovskite series Sr$_x$Ca$_{1-x}$VO$_3$ revealed strong modifications associated with surface contributions. To study the effect of Coulomb correlations in the bulk and at the surface the quasi-particle spectra are evaluated using the dynamical mean field theory. It is shown that as a result of the reduced coordination number of surface atoms correlation effects are stronger at the surface than in the bulk, in agreement with experiment.

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A. Liebsch. 2002-11-13. Surface vs. bulk Coulomb correlations in photoemission spectra of perovskites. https://doi.org/10.1103/physrevlett.90.096401

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