Year: 2004
Type: article
Abstract: It is shown that a variational method with a squeezed state is a useful method for treating many-fermion systems, such as that of the pairing model, that goes beyond the usual Hartree-Fock-Bogoliubov approximation. A pairing-type quasi-spin squeezed state is constructed and adopted as a trial state in this variational method. By using this state, quantum fluctuations are taken into account. As a possible extension to the O(4) model, prospective squeezed states are investigated and its usefulness is discussed. From the viewpoint of the variational approach with a suitable trial state, a fermionic squeezed state is constructed and it is used to obtain a good result for the ground state energy in the O(4) model, while the direct product of two quasi-spin squeezed states based on the algebraic structure does not give a good approximation.
Source: Progress of Theoretical Physics
DOI: 10.1143/ptp.112.583
Authors: H. Akaike, Y. Tsue, S. Nishiyama
Institutions: University of Kochi, Kōchi University
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2170656229