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arXiv · 0908.0048

Origin of infrared peaks in the optical conductivity of ytterbium compounds

Shin-ichi Kimura
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Abstract

We have calculated optical conductivity [$σ(ω)$] spectra of ytterbium compounds (YbAl$_3$, YbAl$_2$, YbCu$_2$Si$_2$, YbNi$_2$Ge$_2$, YbInCu$_4$, YbRh$_2$Si$_2$, YbIr$_2$Si$_2$, and YbB$_{12}$) based on the direct interband transition derived from first-principle band calculation and compared the results with the experimentally obtained $σ(ω)$ spectra. The spectral feature of a peak in the middle-infrared region (mid-IR peak) and a shoulder structure in the far-infrared region (far-IR shoulder) in the experimental $σ(ω)$ spectra can be described by the band calculation with a common renormalization factor. This result indicates that the infrared spectra of Yb compounds originate from the interband transition from the Yb $4f$ state but that the Yb $4f$ state shifts to the Fermi level with strong electron correlation.

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Shin-ichi Kimura. 2009-08-01. Origin of infrared peaks in the optical conductivity of ytterbium compounds. https://doi.org/10.1103/physrevb.80.073103

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