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$β$-NMR of Isolated $^{8}$Li$^{+}$ Implanted into a Thin Copper Film

Z. Salman·A. I. Mansour·K. H. Chow·M. Beaudoin·I. Fan·J. Jung·T. A. Keeler·R. F. Kiefl·C. D. P. Levy·R. C. Ma·G. D. Morris·T. J. Parolin·D. Wang·W. A. MacFarlane
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Abstract

Depth-controlled $β$-NMR was used to study highly spin-polarized $^8$Li in a Cu film of thickness 100 nm deposited onto a MgO substrate. The positive Knight Shifts and spin relaxation data show that $^8$Li occupies two sites at low temperatures, assigned to be the substitutional ($S$) and octahedral ($O$) interstitial sites. Between 50 to 100 K, there is a site change from $O$ to $S$. The temperature dependence of the Knight shifts and spin-lattice relaxation rates at high temperatures, i.e. when all the Li are in the $S$ site, is consistent with the Korringa Law for a simple metal.

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Z. Salman, A. I. Mansour, K. H. Chow, M. Beaudoin, I. Fan, J. Jung, T. A. Keeler, R. F. Kiefl, C. D. P. Levy, R. C. Ma, G. D. Morris, T. J. Parolin, D. Wang, W. A. MacFarlane. 2006-12-29. $β$-NMR of Isolated $^{8}$Li$^{+}$ Implanted into a Thin Copper Film. https://doi.org/10.1103/physrevb.75.073405

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