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arXiv · 1011.1436

Screening in YBCO at large wave vectors

Simo Huotari·J. Aleksi Soininen·György Vankó·Giulio Monaco·Valerio Olevano
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Abstract

We present experimental inelastic x-ray scattering (IXS) and ab initio time-dependent density-functional-theory (TDDFT) studies of YBa2Cu3O7-δ. The response of the low-lying Ba 5p and Y 4p core electrons is shown to interact strongly with the Cu 3d and O 2p excitations, with important consequences on screening. The agreement between IXS and TDDFT results is excellent, apart from a new type of excitations, mainly related to loosely bound Ba electrons and significantly affected by correlations. This points to correlation mechanisms not fully described by TDDFT that might have a role in giving rise to antiscreening.

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Simo Huotari, J. Aleksi Soininen, György Vankó, Giulio Monaco, Valerio Olevano. 2010-11-05. Screening in YBCO at large wave vectors. https://doi.org/10.1103/physrevb.82.064514

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