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arXiv · 1010.0180

Unravelling the glue and the competing order in superconducting cuprates

S. Caprara·C. Di Castro·B. Muschler·R. Hackl·M. Lambacher·A. Erb·S. Komiya·Y. Ando·M. Grilli
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Abstract

We present Raman scattering experiments in ${\rm La_{2-x}Sr_xCuO_4}$ single crystals at various doping levels x and compare the results with theoretical predictions obtained assuming an interaction mediated by spin and charge fluctuations. The light-scattering selection rules allow us to disentangle their respective contributions. We find that the glue spectral function is spin-dominated at low doping while the contribution of charge fluctuations becomes dominant around optimal doping. This indicates that the fluctuations of a nearly ordered state with coexisting spin and charge order support the superconducting pairing.

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S. Caprara, C. Di Castro, B. Muschler, R. Hackl, M. Lambacher, A. Erb, S. Komiya, Y. Ando, M. Grilli. 2010-10-06. Unravelling the glue and the competing order in superconducting cuprates. https://arxiv.org/abs/1010.0180

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