2001/08/31 by P. M. Singer, Philip M. Singer, A. W. Hunt +2 · 3 citations
Earth and Planetary Sciences · Physics and Astronomy · #Advanced Condensed Matter Physics #High-pressure geophysics and materials #Physics of Superconductivity and Magnetism #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.88.047602
Accepted for publication in Physical Review Letters
arxiv created 2001/12/17 · openalex publication_date 2002/01/15 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We report experimental evidence for the spatial variation of hole concentration xhole in the high Tc superconductor La_2\ensuremath-xSrxCuO4 ( 0.04\ensuremath≤x\ensuremath≤0.16) via 63Cu NQR using 63Cu isotope enriched samples. We demonstrate that the extent of the spatial variation of the local hole concentration \ensuremathΔxhole is reflected on 631/T1 and deduce the temperature dependence. \ensuremathΔxhole increases below 500--600 K, and reaches values as large as \ensuremathΔxhole/x\ensuremath∼0.5 below \ensuremath∼150K. We estimate the length scale of the spatial variation in xhole to be Rhole\ensuremath\gtrsim3nm from an analysis of the NQR spectrum.