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arXiv · 1902.06367

Evidence for gradual evolution of low-energy fluctuations underlying the first-order structural and valence order in YbPd

R. Nakanishi·T. Fujii·Y. Nakai·K. Ueda·M. Hirata·K. Oyama·A. Mitsuda·H. Wada·T. Mito
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Abstract

The valence orders at $T_a=125$ K and $T_b=105$ K in the cubic compound YbPd have been investigated by $^{105}$Pd-nuclear magnetic resonance (NMR) measurements. Significant decrease in the density of states at the Fermi energy below $T_a$ is evident from the measurement of nuclear spin lattice relaxation rate $1/T_1$, suggesting that the instabilities of Fermi surface are associated with the transitions. Moreover we observed the unusual evolution of low-energy fluctuations toward the valence transition at $T_a$ behind its drastic first-order nature. The structural transition accompanying the valence order may occur as a result of cooperative effect of Fermi surface and valence instabilities.

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R. Nakanishi, T. Fujii, Y. Nakai, K. Ueda, M. Hirata, K. Oyama, A. Mitsuda, H. Wada, T. Mito. 2019-02-18. Evidence for gradual evolution of low-energy fluctuations underlying the first-order structural and valence order in YbPd. https://arxiv.org/abs/1902.06367

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