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Correlation length in cuprates deduced from the impurity-induced magnetization

S. Ouazi·J. Bobroff·H. Alloul·W. A. MacFarlane
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Abstract

We report a new multi-nuclei based NMR method which allows us to image the staggered polarization induced by nonmagnetic Li impurities in underdoped O6.6 and slightly overdoped O7 YBa2Cu3O6+y above T_C. The spatial extension of the polarization xi_imp approximately follows a Curie law, increasing up to six lattice constants at T=80K at O6.6 in the pseudogap regime. Near optimal doping, the staggered magnetization has the same shape, with xi_imp reduced by a factor 2. xi_imp is argued to reveal the intrinsic magnetic correlation length of the pure system. It is found to display a smooth evolution through the pseudogap regime.

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S. Ouazi, J. Bobroff, H. Alloul, W. A. MacFarlane. 2004-09-13. Correlation length in cuprates deduced from the impurity-induced magnetization. https://doi.org/10.1103/physrevb.70.104515

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