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$β$-Detected NMR of $^8$Li in the Normal State of 2H-NbSe$_2$

D. Wang·M. D. Hossain·Z. Salman·D. Arseneau·K. H. Chow·S. Daviel·T. A. Keeler·R. F. Kiefl·S. R. Kreitzman·C. D. P. Levy·G. D. Morris·R. I. Miller·W. A. MacFarlane·T. J. Parolin·H. Saadaoui
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Abstract

$β$-NMR of isolated $^8$Li has been investigated in the normal state of 2H-NbSe$_2$. In a high magnetic field of 3T a single resonance is observed with a Gaussian line width of 3.5 kHz. The line shape varies weakly as function of magnetic field and temperature but has a strong orientation dependence. The nuclear electric quadrupole splitting is unresolved implying that the electric field gradients are 10-100 times smaller than in other non-cubic crystals. The nuclear spin relaxation rate is also anomalously small but varies linearly with temperature as expected for Korringa relaxation in a metal. These results suggest that Li adopts an interstitial position between the weakly coupled NbSe$_2$ layers and away from the conduction band.

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D. Wang, M. D. Hossain, Z. Salman, D. Arseneau, K. H. Chow, S. Daviel, T. A. Keeler, R. F. Kiefl, S. R. Kreitzman, C. D. P. Levy, G. D. Morris, R. I. Miller, W. A. MacFarlane, T. J. Parolin, H. Saadaoui. 2005-11-14. $β$-Detected NMR of $^8$Li in the Normal State of 2H-NbSe$_2$. https://doi.org/10.1016/j.physb.2005.11.064

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