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Local moment fluctuations in an optimally-doped high Tc superconductor

D. Reznik·J. -P. Ismer·I. Eremin·L. Pintschovius·M. Arai·Y. Endoh·T. Masui·S. Tajima
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Abstract

We present results of neutron scattering experiments on YBa2Cu3O6.95 (Tc=93K). Our results indicate that magnetic collective modes due to correlated local moments are present both above and below Tc in optimally doped YBCO. The magnon-like modes are robust and not overdamped by itinerant particle-hole excitations, which may point at a substantial static or slowly fluctuating charge inhomogeneity. We compare the experimental results to predictions of the Fermi liquid (FL) theory in the Random Phase Approximation (RPA).

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D. Reznik, J. -P. Ismer, I. Eremin, L. Pintschovius, M. Arai, Y. Endoh, T. Masui, S. Tajima. 2008-09-06. Local moment fluctuations in an optimally-doped high Tc superconductor. https://arxiv.org/abs/cond-mat/0610755

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