Improvement to the Projected BCS Approximation

38th Symposium on Nuclear Physics

Pittel, S.^1 ; Dukelsky, J.^2 ; Esebbag, C.^3

Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark

DE

19716, United States^1

Instituto de Estructura de la Materia, CSIC, Serrano 123, Madrid

28006, Spain^2

Departamento de Matemáticas, Universidad de Alcalá, Alcalá de Henares

28871, Spain^3

关键词: Approximate treatment;    Degenerate levels;    Half-filling;    Richardson model;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/639/1/012009/pdf
DOI  :  10.1088/1742-6596/639/1/012009

来源: IOP

【 摘 要 】

We consider the structure of the number projected BCS wave function in the particle-hole basis, and use it to study several approximate treatments of pairing. The analysis is carried out for the exactly solvable Richardson model involving a pure pairing hamiltonian acting in a space of equally spaced doubly degenerate levels at half filling.