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Pressure dependence of the resistivity around valence transition based on 1/N-expansion study for extended Anderson lattice

Yasutaka Nishida·Tomokazu Ookubo
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Abstract

We investigate the behavior of the resistivity around valence transition in the one-dimensional extended periodic Anderson model (PAM) with the Coulomb repulsion between f and conduction electron U_fc. By using 1/N-expansion in the leading order in (1/N)^0, where N is the spin-orbital degeneracy of f-electrons, valence transition happens at critical U_fc with increasing the atomic f-level as seen in the previous work. We calculate the resistivity whole temperature range around valence transition based on the extended PAM including the crystal field and investigate how the physical properties such as Kondo temperature is modified by additional U_fc interaction. As a result, the double peak structure of the electrical resistivity fades away rapidly by the rapid increase of the Kondo temperature.

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Yasutaka Nishida, Tomokazu Ookubo. 2006-07-31. Pressure dependence of the resistivity around valence transition based on 1/N-expansion study for extended Anderson lattice. https://arxiv.org/abs/cond-mat/0607373

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