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Specific Heat of the Periodic Anderson Model: From Weak to Strong Coupling

N. M. R. Peres·P. D. Sacramento·M. A. N. Araujo
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Abstract

We study the temperature dependence of the specific heat in the periodic Anderson model as function of the on-site Coulomb interaction, hybridization, and position of the f-electrons energy level. At strong coupling (U=infinity) we use slave bosons, whereas at weak coupling we use a simple Hartree-Fock decomposition. We find that both in the strong and weak coupling limits the specific heat of the system presents a multiple peak structure in a mean field treatment. We believe these features to be related to band-shape effects. The temperature evolution of the low-temperature peak position on the model parameters for the non-half filled non-symmetric case is discussed.

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N. M. R. Peres, P. D. Sacramento, M. A. N. Araujo. 2001-09-20. Specific Heat of the Periodic Anderson Model: From Weak to Strong Coupling. https://doi.org/10.1103/physrevb.64.113104

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