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Resonant Inelastic X-Ray Scattering from Valence Excitations in Insulating Copper-Oxides

P. Abbamonte·C. A. Burns·E. D. Isaacs·P. M. Platzman·L. L. Miller·S. W. Cheong·M. V. Klein
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Abstract

We report resonant inelastic x-ray measurements of insulating La$_2$CuO$_4$ and Sr$_2$CuO$_2$Cl$_2$ taken with the incident energy tuned near the Cu K absorption edge. We show that the spectra are well described in a shakeup picture in 3rd order perturbation theory which exhibits both incoming and outgoing resonances, and demonstrate how to extract a spectral function from the raw data. We conclude by showing {\bf q}-dependent measurements of the charge transfer gap.

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P. Abbamonte, C. A. Burns, E. D. Isaacs, P. M. Platzman, L. L. Miller, S. W. Cheong, M. V. Klein. 1999-06-16. Resonant Inelastic X-Ray Scattering from Valence Excitations in Insulating Copper-Oxides. https://doi.org/10.1103/physrevlett.83.860

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