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Observation of a new excitation in the mixed-valent state of YbInCu_4

S. R. Garner·Y. W. Rodriguez·Z. Schlesinger·B. Bucher·Z. Fisk·J. L. Sarrao
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Abstract

Infrared measurements are used to obtain conductivity as a function of temperature and frequency in YbInCu_4, which exhibits an isostructural transition to a mixed-valent state at T_v \simeq 42 K. In addition to a gradual loss of spectral weight with decreasing temperature extending up to 1.5 eV, sharp resonances appear in the mixed-valent state at 0 and 0.25 eV . These features may be key to understanding both YbInCu_4 and the nature of the mixed-valent Kondo state.

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S. R. Garner, Y. W. Rodriguez, Z. Schlesinger, B. Bucher, Z. Fisk, J. L. Sarrao. 1999-10-29. Observation of a new excitation in the mixed-valent state of YbInCu_4. https://arxiv.org/abs/cond-mat/9910485

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