Charge fluctuations, spin fluctuations, and superconductivity in the Anderson lattice model of heavy-fermion systems
We determine the quasiparticle-quasiparticle interaction within the U..-->..infinity Anderson lattice model via an auxiliary boson (1N) expansion to order (1N)/sup 2/. At leading order the interaction which is mediated by the exchange of a single zero-frequency fluctuation of the Bose field is repulsive in the p channel and attractive in the d channel. The dominant contribution to the interaction at order (1N)/sup 2/, which is due to spin fluctuations involving high-frequency, ..omega..>T/sub K/, fluctuations of the Bose field, is attractive in both p and d channels. The strength of this term relative to the charge fluctuation contribution is of order (m/sup */m)ln/sup -2/(Nm/sup */m), where m/sup */ is the heavy-fermion mass. Thus, for parameters corresponding to the majority of systems of interest, pairing in this model is allowed in both p and d channels;the origin of the attractive interaction, as in /sup 3/He, is in the exchange of spin fluctuations
- Research Organization:
- Department of Physics, Brown University, Providence, Rhode Island 02912
- OSTI ID:
- 5154838
- Journal Information:
- Phys. Rev. B: Condens. Matter; (United States), Vol. 37:7
- Country of Publication:
- United States
- Language:
- English
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