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arXiv · 0809.0044

Effect of Rattling Phonons on Sommerfeld Constant

Takashi Hotta
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Abstract

By employing a numerical renormalization group technique, we evaluate electronic specific heat coefficient $γ$ of the Anderson model coupled with local anharmonic phonons for the oscillation of a caged atom. For the rattling-type cage potential with a flat and wide region in the bottom, we find that phonon-mediated attraction is largely enhanced. When the potential shape is deformed from the rattling type, there occurs a cancellation between Coulomb repulsion and the phonon-mediated attraction. In such a situation, spin and charge fluctuations are comparable to each other, leading to the realization of exotic electron-phonon complex state with large and magnetically robust $γ$.

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Takashi Hotta. 2008-08-30. Effect of Rattling Phonons on Sommerfeld Constant. https://doi.org/10.1143/jpsj.77.103711

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