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Dynamics of the Local Moment Induced by Nonmagnetic Defects in Cuprates

W. A. MacFarlane·J. Bobroff·H. Alloul·P. Mendels·N. Blanchard·G. Collin·J. -F. Marucco
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Abstract

We present a study of the spin dynamics of magnetic defects induced by Li substitution of the plane Cu in the normal state of YBa$_2$Cu$_3$O$_{6+x}$. The fluctuations of the coupled Cu magnetic moments in the vicinity of Li are probed by near-neighbour $^{89}$Y {\it and} $^7$Li NMR spin lattice relaxation. The data indicates that the magnetic perturbation fluctuates as a single entity with a correlation time $τ$ which scales with the local static susceptibility. This behaviour is reminiscent of the low $T$ Kondo state of magnetic impurities in conventional metals. Surprisingly it extends well above the ``Kondo'' temperature for the underdoped pseudogapped case.

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W. A. MacFarlane, J. Bobroff, H. Alloul, P. Mendels, N. Blanchard, G. Collin, J. -F. Marucco. 2000-06-12. Dynamics of the Local Moment Induced by Nonmagnetic Defects in Cuprates. https://doi.org/10.1103/physrevlett.85.1108

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