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(63)Cu NQR Evidence for Spatial Variation of Hole Concentration in La(2-x)Sr(x)CuO(4)

P. M. Singer·A. W. Hunt·T. Imai
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Abstract

We report experimental evidence for the spatial variation of hole concentration x_(hole) in the high Tc superconductor La(2-x)Sr(x)CuO(4) (0.04 <= x <= 0.16) by using (63)Cu NQR for (63)Cu isotope enriched samples. We demonstrate that the extent of the spatial variation of the local hole concentration D(x)_(hole) is reflected on (63)1/T1 and deduce the temperature dependence. D(x)_(hole) increases below 500 - 600K, and reaches values as large as D(x)_(hole)/x ~ 0.5 below ~ 150K. We estimate the length scale of the spatial variation in x_(hole) to be R_(hole) >~ 3nm from analysis of the NQR spectrum.

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P. M. Singer, A. W. Hunt, T. Imai. 2001-12-17. (63)Cu NQR Evidence for Spatial Variation of Hole Concentration in La(2-x)Sr(x)CuO(4). https://doi.org/10.1103/physrevlett.88.047602

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