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An Orbitally Degenerate Spin Fluctuation Model for Heavy Fermion Superconductivity

M. R. Norman
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Abstract

In this paper, a generalization of standard spin fluctuation theory is considered by replacing the simple Hubbard interaction by the screened Hartree-Fock interaction for f electrons. This model is then used in both an LS and a JJ coupling scheme to construct the particle-particle scattering vertex in an on-site approximation. This vertex is shown to lead to an instability for a superconducting pair state which obeys Hunds rules, with L=5, S=1, and J=4. The degeneracy of this state is broken by anisotropy of the quasiparticle wavefunctions. Detailed calculations are presented for the case of $UPt_3$.

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M. R. Norman. 1994-03-03. An Orbitally Degenerate Spin Fluctuation Model for Heavy Fermion Superconductivity. https://doi.org/10.1103/physrevb.50.6904

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