Resonating Hartree-Bogoliubov Theory for a Superconducting Fermion System with Large Quantum Fluctuations
نویسنده
چکیده
We develop a general theory to describe a superconducting Fermion system with large quantum fluctuations. The theory is a direct extension of the resonating Hartree-Fock (HF) theory to the Hartree·Bogoliubov case including pair correlations. We start with an exact coherent state representation of a superconducting Fermion system on 'a special orthogonal group. A state with large quantum fluctuations is approximated by a superposition of non·orthogonal Hartree-Bogoliubov (HB) wave functions with different correlation structures. We obtain the variational equations to determine the coefficients of configuration mixing and the orbitals in the resonating HB wave functions.
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