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arXiv · 1111.3225

Hole-depletion of ladders in Sr$_{14}$Cu$_{24}$O$_{41}$ induced by correlation effects

V. Ilakovac·C. Gougoussis·M. Calandra·N. B. Brookes·V. Bisogni·S. G. Chiuzbaian·J. Akimitsu·O. Milat·S. Tomić·C. F. Hague
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Abstract

The hole distribution in Sr$_{14}$Cu$_{24}$O$_{41}$ is studied by low temperature polarization dependent O K Near-Edge X-ray Absorption Fine Structure measurements and state of the art electronic structure calculations that include core-hole and correlation effects in a mean-field approach. Contrary to all previous analysis, based on semi-empirical models, we show that correlations and antiferromagnetic ordering favor the strong chain hole-attraction. For the remaining small number of holes accommodated on ladders, leg-sites are preferred to rung-sites. The small hole affinity of rung-sites explains naturally the 1D - 2D cross-over in the phase diagram of (La,Y,Sr,Ca)$_{14}$Cu$_{24}$O$_{41}$

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V. Ilakovac, C. Gougoussis, M. Calandra, N. B. Brookes, V. Bisogni, S. G. Chiuzbaian, J. Akimitsu, O. Milat, S. Tomić, C. F. Hague. 2011-11-14. Hole-depletion of ladders in Sr$_{14}$Cu$_{24}$O$_{41}$ induced by correlation effects. https://doi.org/10.1103/physrevb.85.075108

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