Correlation length in cuprate superconductors deduced from impurity-induced magnetization
نویسندگان
چکیده
We report a new multinuclei based nuclear magnetic resonance method which allows us to image the staggered polarization induced by nonmagnetic Li impurities in underdoped sO6.6d and slightly overdoped sO7d YBa2Cu3O6+y above TC. The spatial extension of the polarization jimp approximately follows a Curie law, increasing up to six lattice constants at 80 K at O6.6 in the pseudogap regime. Near optimal doping, the staggered magnetization has the same shape, with jimp reduced by a factor 2. jimp 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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