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arXiv · 1510.04788

DMFT Study for Valence Fluctuations in the Extended Periodic Anderson Model

Ryu Shinzaki·Joji Nasu·Akihisa Koga
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Abstract

We study valence fluctuations at finite temperatures in the extended periodic Anderson model, where the Coulomb interaction between conduction and localized $f$-electrons is taken into account, using dynamical mean-field theory combined with the continuous-time quantum Monte Carlo (CT-QMC) method. The valence transition with the hysteresis is clearly found, indicating the first-order phase transition between the Kondo and mixed-valence states. We demonstrate that spin correlation rapidly develops when the system approaches the valence transition point. The comparison of the impurity solvers, %: the CT-QMC, non-crossing approximation, and one-crossing approximation, is also addressed.

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Ryu Shinzaki, Joji Nasu, Akihisa Koga. 2015-10-16. DMFT Study for Valence Fluctuations in the Extended Periodic Anderson Model. https://doi.org/10.1088/1742-6596%2F683%2F1%2F012041

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