Pair condensation in a finite Fermi system
Abstract
The lowest seniorityzero eigenstates of an exactly solvable multilevel pairing Hamiltonian for a finite Fermi system are examined at different pairing regimes. After briefly reviewing the form of the eigenstates in the Richardson formalism, we discuss a different representation of these states in terms of the collective pairs resulting from the diagonalization of the Hamiltonian in a space of two degenerate timereversed fermions. We perform a twofold analysis by working both in the fermionic space of these collective pairs and in a space of corresponding elementary bosons. On the fermionic side, we monitor the variations which occur, with increasing the pairing strength, in the structure of both these collective pairs and the lowest eigenstates. On the bosonic side, after reviewing a fermionboson mapping procedure, we construct exact images of the fermion eigenstates and study their wave function. The analysis allows a close examination of the phenomenon of pair condensation in a finite Fermi system and gives new insights into the evolution of the lowest (seniorityzero) excited states of a pairing Hamiltonian from the unperturbed regime up to a strongly interacting one.
 Authors:
 Istituto Nazionale di Fisica NucleareSezione di Catania, Via S. Sofia 64, I95123 Catania (Italy)
 Publication Date:
 OSTI Identifier:
 20995276
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. C, Nuclear Physics; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevC.75.054314; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; BOSONS; EIGENSTATES; EXACT SOLUTIONS; EXCITED STATES; FERMIONS; HAMILTONIANS; WAVE FUNCTIONS
Citation Formats
Sambataro, M. Pair condensation in a finite Fermi system. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVC.75.054314.
Sambataro, M. Pair condensation in a finite Fermi system. United States. doi:10.1103/PHYSREVC.75.054314.
Sambataro, M. 2007.
"Pair condensation in a finite Fermi system". United States.
doi:10.1103/PHYSREVC.75.054314.
@article{osti_20995276,
title = {Pair condensation in a finite Fermi system},
author = {Sambataro, M.},
abstractNote = {The lowest seniorityzero eigenstates of an exactly solvable multilevel pairing Hamiltonian for a finite Fermi system are examined at different pairing regimes. After briefly reviewing the form of the eigenstates in the Richardson formalism, we discuss a different representation of these states in terms of the collective pairs resulting from the diagonalization of the Hamiltonian in a space of two degenerate timereversed fermions. We perform a twofold analysis by working both in the fermionic space of these collective pairs and in a space of corresponding elementary bosons. On the fermionic side, we monitor the variations which occur, with increasing the pairing strength, in the structure of both these collective pairs and the lowest eigenstates. On the bosonic side, after reviewing a fermionboson mapping procedure, we construct exact images of the fermion eigenstates and study their wave function. The analysis allows a close examination of the phenomenon of pair condensation in a finite Fermi system and gives new insights into the evolution of the lowest (seniorityzero) excited states of a pairing Hamiltonian from the unperturbed regime up to a strongly interacting one.},
doi = {10.1103/PHYSREVC.75.054314},
journal = {Physical Review. C, Nuclear Physics},
number = 5,
volume = 75,
place = {United States},
year = 2007,
month = 5
}

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