$β$ NMR study of Isolated $^8$Li in the enhanced paramagnet Platinum
cond-mat.str-el
/ Authors
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
and 6 more authors
G. D. Morris, M. R. Pearson, H. Saadaoui, Q. Song, D. Wang, W. A. MacFarlane
/ Abstract
We report β detected nuclear magnetic resonance (βNMR) measurements of 8Li+ implanted into high purity Pt. The frequency of the 8Li βNMR 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+.