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Observation of New Incommensurate Magnetic Correlations at the Lower Critical Concentration for Superconductivity (x=0.05) in La(2-x)Sr(x)CuO4

S. Wakimoto·R. J. Birgeneau·Y. Endoh·P. M. Gehring·K. Hirota·M. A. Kastner·S. H. Lee·Y. S. Lee·G. Shirane·S. Ueki·K. Yamada
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Abstract

Neutron-scattering experiments have been performed on lightly-doped La(2-x)Sr(x)CuO4 single crystals in both the insulating (x=0.03,0.04,0.05) and superconducting (x=0.06) regions. Elastic magnetic peaks are observed at low temperatures in all samples with the maximum peak linewidth occuring at the critical concentration x_c=0.05. New incommensurate peaks are observed only at x=0.05, the positions of which are rotated by 45 degrees in reciprocal space about (pi,pi) from those observed for x>=0.06 in the superconducting phase.

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S. Wakimoto, R. J. Birgeneau, Y. Endoh, P. M. Gehring, K. Hirota, M. A. Kastner, S. H. Lee, Y. S. Lee, G. Shirane, S. Ueki, K. Yamada. 1999-04-16. Observation of New Incommensurate Magnetic Correlations at the Lower Critical Concentration for Superconductivity (x=0.05) in La(2-x)Sr(x)CuO4. https://doi.org/10.1103/physrevb.60.r769

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