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arXiv · 1308.4220

Stability of three-fermion clusters with finite range of attraction

Pavel E. Kornilovitch
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Abstract

Three quantum particles with on-site repulsion and nearest-neighbour attraction on a one-dimensional lattice are considered. The three-body Schroedinger 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-1/2 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.

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Pavel E. Kornilovitch. 2013-08-20. Stability of three-fermion clusters with finite range of attraction. https://doi.org/10.1209/0295-5075%2F103%2F27005

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