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arXiv · 0902.1468

Hybridization-driven gap in U3Bi4Ni3: a 209Bi NMR/NQR study

S. -H. Baek·N. J. Curro·T. Klimczuk·H. Sakai·E. D. Bauer·F. Ronning·J. D. Thompson
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Abstract

We report 209Bi NMR and NQR measurements on a single crystal of the Kondo insulator U3Bi4Ni3. The 209Bi nuclear spin-lattice relaxation rate ($T_1^{-1}$) shows activated behavior and is well-fit by a spin gap of 220 K. The 209Bi Knight shift (K) exhibits a strong temperature dependence arising from 5f electrons, in which K is negative at high temperatures and increases as the temperature is lowered. Below 50 K, K shows a broad maximum and decreases slightly upon further cooling. Our data provide insight into the evolution of the hyperfine fields in a fully gapped Kondo insulator based on 5f electron hybridization.

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S. -H. Baek, N. J. Curro, T. Klimczuk, H. Sakai, E. D. Bauer, F. Ronning, J. D. Thompson. 2009-05-20. Hybridization-driven gap in U3Bi4Ni3: a 209Bi NMR/NQR study. https://doi.org/10.1103/physrevb.79.195120

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