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arXiv · 2106.00211

Evolution of the metallic state of LaNiO$_3$/LaAlO$_3$ superlattices measured by $^8$Li $\beta$-detected NMR

V. L. Karner·A. Chatzichristos·D. L. Cortie·D. Fujimoto·R. F. Kiefl·C. D. P. Levy·R. Li·R. M. L. McFadden·G. D. Morris·M. R. Pearson·E. Benckiser·A. V. Boris·G. Cristiani·G. Logvenov·B. Keimer·W. A. MacFarlane
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Abstract

Using ion-implanted $^8$Li $\beta$-detected NMR, we study the evolution of the correlated metallic state of LaNiO$_3$ in a series of LaNiO$_3$/LaAlO$_3$ superlattices as a function of bilayer thickness. Spin-lattice relaxation measurements in an applied field of 6.55 T reveal two equal amplitude components: one with metallic ($T$-linear) $1/T_{1}$, and a second with a more complex $T$-dependence. The metallic character of the slow relaxing component is only weakly affected by the LaNiO$_3$ thickness, while the fast component is much more sensitive, exhibiting the opposite temperature dependence (increasing towards low $T$) in the thinnest, most magnetic samples. The origin of this bipartite relaxation is discussed.

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V. L. Karner, A. Chatzichristos, D. L. Cortie, D. Fujimoto, R. F. Kiefl, C. D. P. Levy, R. Li, R. M. L. McFadden, G. D. Morris, M. R. Pearson, E. Benckiser, A. V. Boris, G. Cristiani, G. Logvenov, B. Keimer, W. A. MacFarlane. 2021-06-01. Evolution of the metallic state of LaNiO$_3$/LaAlO$_3$ superlattices measured by $^8$Li $\beta$-detected NMR. https://doi.org/10.1103/physrevb.104.205114

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