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Magnetic and superconducting instabilities in the periodic Anderson model: an RPA stud

N. M. R. Peres·M. A. N. Araujo
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Abstract

We study the magnetic and superconducting instabilities of the periodic Anderson model with infinite Coulomb repulsion U in the random phase approximation. The Neel temperature and the superconducting critical temperature are obtained as functions of electronic density (chemical pressure) and hybridization V (pressure). It is found that close to the region where the system exhibits magnetic order the critical temperature T_c is much smaller than the Neel temperature, in qualitative agreement with some T_N/T_c ratios found for some heavy-fermion materials. In our study, all the magnetic and superconducting physical behaviour of the system has its origin in the fluctuating boson fields implementing the infinite on-site Coulomb repulsion among the f-electrons.

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N. M. R. Peres, M. A. N. Araujo. 2003-03-20. Magnetic and superconducting instabilities in the periodic Anderson model: an RPA stud. https://doi.org/10.1088/0953-8984%2F14%2F22%2F310

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