J. Phys. Soc. Jpn. 75S (2006) pp. 127-129  |Previous Article| |Next Article|  |Table of Contents|
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Proc. of 5th Int. Symposium on ASR-WYP-2005 – Advances in the Physics and Chemistry of Actinide Compounds –

NMR Study of Antiferromagnet UPtGa₅

Shinsaku Kambe, Hironori Sakai, Yo Tokunaga, Tatsuya Fujimoto, Harukazu Kato, Russell E. Walstedt, Shugo Ikeda, Tatsuma D. Matsuda, Yoshinori Haga and Yoshichika Ōnuki¹

We report spin–lattice relaxation time (T₁) measurements at Ga and Pt sites in a single crystal sample of an itinerant antiferromagnet UPtGa₅ (T_N=27 K). In the paramagnetic state at high temperatures, the T-dependence of static susceptibility and 1/T₁T at Ga and Pt sites shows a similar behavior, indicating the dynamical susceptibility \textImχ(q,ω) has no strong q-dependence at high temperatures. This behavior suggests a localized character of this compound at high temperatures. Around T_N, 1/T₁T at Ga site increases rapidly due to critical slowing down behavior, in contrast a saturation behavior is observed at Pt site as the antiferromagnetic fluctuation cancels at Pt site. The characteristic spin fluctuation energy Γ is estimated using T₁ and previously obtained hyperfine parameters.

URL: http://jpsj.ipap.jp/link?JPSJS/75S/127/
DOI: 10.1143/JPSJS.75S.127

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