Stability of three-fermion clusters with finite range of attraction
Hewlett-Packard Company - Corvallis, OR, USA
Received: 23 May 2013
Accepted: 17 July 2013
Three quantum particles with on-site repulsion and nearest-neighbour attraction on a one-dimensional lattice are considered. The three-body Schrödinger equation is reduced to a set of single-variable integral equations. Energies of three-particle bound complexes (trions) are found from self-consistency of the approximating matrix equation. In the case of spin- fermions, the ground-state trion energy, the excited-state energies, the trion spectra and stability regions are obtained for total spins S = 1/2 and S = 3/2. In the S = 1/2 sector, a narrow but finite parameter region is identified where the ground state consists of a stable fermion pair and an unbound fermion. Also presented is the reference case of spin-0 bosons.
PACS: 71.10.Li – Excited states and pairing interactions in model systems / 74.90.+n – Other topics in superconductivity (restricted to new topics in section 74)
© EPLA, 2013