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arXiv · 1208.3873

$\beta$ NMR study of Isolated $^8$Li in the enhanced paramagnet Platinum

Oren Ofer·K. H. Chow·I. Fan·M. Egilmez·T. J. Parolin·M. D. Hossain·J. Jung·Z. Salman·R. F. Kiefl·C. D. P. Levy·G. D. Morris·M. R. Pearson·H. Saadaoui·Q. Song·D. Wang·W. A. MacFarlane
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Abstract

We report {\beta} detected nuclear magnetic resonance ({\beta}NMR) measurements of 8Li+ implanted into high purity Pt. The frequency of the 8Li {\beta}NMR resonance and the spin-lattice relaxation rates 1/T1 were measured at temperatures ranging from 3 to 300 K. Remarkably, both the spin-lattice relaxation rate and the Knight shift K depend linearly on temperature T although the bulk susceptibility does not. K is found to scale with the Curie-Weiss dependence of the Pt susceptibility extrapolated to low temperatures. This is attributed to a defect response of the enhanced paramagnetism of Pt, i.e. the presence of the interstitial Li+ locally relieves the tendency for the Curie-Weiss susceptibility to saturate at low T . We propose that the low temperature saturation in \c{hi} of Pt may be related to an interband coupling between the s and d bands that is disrupted locally by the presence of the Li+.

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Oren Ofer, K. H. Chow, I. Fan, M. Egilmez, T. J. Parolin, M. D. Hossain, J. Jung, Z. Salman, R. F. Kiefl, C. D. P. Levy, G. D. Morris, M. R. Pearson, H. Saadaoui, Q. Song, D. Wang, W. A. MacFarlane. 2012-08-19. $\beta$ NMR study of Isolated $^8$Li in the enhanced paramagnet Platinum. https://doi.org/10.1103/physrevb.86.064419

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