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arXiv · 1703.10156

Determination of the nature of fluctuations using $^8Li$ and $^9Li$ $\beta$-NMR and spin-lattice relaxation

A. Chatzichristos·R. M. L. McFadden·V. L. Karner·D. L. Cortie·C. D. P. Levy·W. A. MacFarlane·G. D. Morris·M. R. Pearson·Z. Salman·R. F. Kiefl
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Abstract

We report a comparison of the $1/T_1$ spin lattice relaxation rates (SLR) for $^9Li$ and $^8Li$ in Pt and SrTiO$_{3}$, in order to differentiate between magnetic and electric quadrupolar relaxation mechanisms. In Pt, the ratio of the $1/T_{1}$ spin relaxation rates $R_{Pt}$ was found to be 6.82(29), which is close to but less than the theoretical limit of $\sim7.68$ for pure magnetic relaxation. In SrTiO$_{3}$ this ratio was found to be 2.7(3), which is close but larger than the theoretical limit of $\sim2.14$ expected for pure electric quadrupolar relaxation. These results bring new insight into the nature of the fluctuations in the local environment of implanted $^8Li$ observed by $\beta$-NMR.

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A. Chatzichristos, R. M. L. McFadden, V. L. Karner, D. L. Cortie, C. D. P. Levy, W. A. MacFarlane, G. D. Morris, M. R. Pearson, Z. Salman, R. F. Kiefl. 2017-03-29. Determination of the nature of fluctuations using $^8Li$ and $^9Li$ $\beta$-NMR and spin-lattice relaxation. https://doi.org/10.1103/physrevb.96.014307

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