Schrieffer-Wolff transformation for the Anderson Hamiltonian in a superconductor
A generalized Schrieffer-Wolff transformation is introduced to relate the Anderson impurity model in a superconductor to a Kondo-like Hamiltonian. The effective exchange interactions coupling a magnetic impurity to a Bardeen-Cooper-Schrieffer (BCS) spectrum of electronic excitations are expressed in terms of the superconducting coherence factors. New exchange mechanisms originate from the particle-hole coherence unique to superconductors. These interactions are relevant for large asymmetry in the magnetic limit; they vanish for nonmagnetic impurities and in the symmetric Anderson model, for which the ''normal'' Schrieffer-Wolff coupling constant is recovered. The magnetically induced equal-spin Cooper-pairing correlations are suggested to be relevant for superconducting valence fluctuators and within heavy-fermion superconductivity.
- Research Organization:
- Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801
- OSTI ID:
- 7247190
- Journal Information:
- Phys. Rev. B: Condens. Matter; (United States), Vol. 37:16
- Country of Publication:
- United States
- Language:
- English
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