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Local spin polarization in underdoped cuprates with impurities

G. Khaliullin·R. Kilian·S. Krivenko·P. Fulde
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Abstract

We present a theory of magnetic (Ni) and nonmagnetic (Zn) impurities substituted into planar Cu sites in the normal state of underdoped cuprates exhibiting a spin gap. Both types of impurities induce magnetic moments on neighboring Cu sites. In the case of Ni these moments partially screen the inherent impurity spin, resulting in an effective S=1/2 moment. The characteristic Kondo scale is found to have a power-law dependence on the coupling constant. We investigate the spatial shape of the impurity-induced spin density, taking into account the presence of short-ranged AF correlations, and calculate the ^{17}O NMR line broadening induced by impurity doping.

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G. Khaliullin, R. Kilian, S. Krivenko, P. Fulde. 1998-10-05. Local spin polarization in underdoped cuprates with impurities. https://doi.org/10.1016/s0921-4534(99)00107-0

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