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Hole concentration dependence of the magnetic moment in superconducting and insulating La2-xSrxCuO4

S. Wakimoto·R. J. Birgeneau·Y. S. Lee·G. Shirane
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Abstract

Recent neutron scattering measurements on the La2-xSrxCuO4 system have revealed a drastic change of the incommensurate static spin correlations from diagonal in the insulating region to parallel in the superconducting region. We report the doping dependence of the ordered magnetic moment for the hole concentration region 0.03 <= x <= 0.12, focusing on the relationship between the static magnetism and the superconductivity. The elastic magnetic crosssection decreases monotonically with increasing x for 0.03 <= x <= 0.07. We find that the ordered magnetic moment μvaries from ~0.18 (x=0.03) to \~0.06 μ_B/Cu (x=0.07). No significant anomaly is observed at the insulator-superconductor boundary (x ~ 0.055). The elastic magnetic crosssection is enhanced in the vicinity of x=0.12 whose resolution limited width peaks are observed in neutron scattering measurements and where the apparent magntic and superconducting transitions coincide.

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S. Wakimoto, R. J. Birgeneau, Y. S. Lee, G. Shirane. 2001-03-05. Hole concentration dependence of the magnetic moment in superconducting and insulating La2-xSrxCuO4. https://doi.org/10.1103/physrevb.63.172501

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