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Anomalous NMR Spin-Lattice Relaxation in SrB_{6} and Ca_{1-x}La_{x}B_{6}

J. L. Gavilano·Sh. Mushkolaj·D. Rau·H. R. Ott·A. Bianchi·D. P. Young·Z. Fisk
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Abstract

We report the results of {11}B nuclear magnetic resonance (NMR) measurements of SrB_{6} and Ca_{0.995}La_{0.05}B_{6} below room temperature. Although the electrical resistivities of these two materials differ substantially, their {11}B-NMR responses exhibit some strikingly common features. Both materials exhibit ferromagnetic order, but their {11}B-NMR spectra reveal very small hyperfine fields at the Boron sites. The spin lattice relaxation T_{1}^{-1} varies considerably with external field but changes with temperature only below a few K. We discuss these unusual results by considering various different scenarios for the electronic structure of these materials.

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J. L. Gavilano, Sh. Mushkolaj, D. Rau, H. R. Ott, A. Bianchi, D. P. Young, Z. Fisk. 2001-01-31. Anomalous NMR Spin-Lattice Relaxation in SrB_{6} and Ca_{1-x}La_{x}B_{6}. https://doi.org/10.1103/physrevb.63.140410

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