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arXiv · 1901.01333

Site Specific Knight Shift Measurements of the Dilute Kondo lattice System Ce$_{1-x}$La$_x$CoIn$_5$

M. Lawson·B. T. Bush·A. C. Shockley·C. Capan·Z. Fisk·N. J. Curro
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Abstract

$^{115}$In Nuclear magnetic resonance data are presented for a series of Ce$_{1-x}$La$_x$CoIn$_5$ crystals with different La dilutions, $x$. Multiple In(1) sites associated with different numbers of nearest-neighbor cerium atoms exhibit different Knight shifts and spin lattice relaxation rates. Analysis of the temperature dependence of these sites reveals both an evolution of the heavy electron coherence as a function of dilution, as well as spatial inhomogeneity associated with a complete suppression of antiferromagnetic fluctuations in the vicinity of the La sites. Quantum critical fluctuations persist within disconnected Ce clusters with dilution levels up to 75%, despite the fact that specific heat shows Fermi liquid behavior in dilute samples.

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M. Lawson, B. T. Bush, A. C. Shockley, C. Capan, Z. Fisk, N. J. Curro. 2019-01-04. Site Specific Knight Shift Measurements of the Dilute Kondo lattice System Ce$_{1-x}$La$_x$CoIn$_5$. https://doi.org/10.1103/physrevb.99.165106

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