A Constrained Hartree-Fock-Bogoliubov Equation Derived from the Double Variational Method
Naoki Onishi, Takatoshi Horibata · Progress of Theoretical Physics · 1980
The double variational method is applied to the intrinsic state of the generalized BCS wave function. A constrained Hartree-Fock-Bogoliubov equation is derived explicitly in the form of an eigenvalue equation. A method of obtaining approximate overlap and energy overlap integrals is proposed. This will help development of numerical calculations of the angular momentum projection method, especially for general intrinsic wave functions without any symmetry restrictions.