Abstract
The formation of bound states of holes in an antiferromagnetic spin-1/2 background is studied using numerical techniques applied to the t-J Hamiltonian on clusters with up to 26 sites. An analysis of the binding energy as a function of cluster size suggests that a two-hole bound state is formed for couplings larger than a ‘‘critical’’ value J/t The symmetry of the bound state is -. We also observed that its ‘‘quasiparticle’’ weight (defined in the text), is finite for coupling J/t≥J/t. Thus, in the region J/t≥J/t the bound state of two holes behaves like a quasiparticle with charge Q=2e, spin S=0, and - internal symmetry. The relation with recent ideas that have suggested the possibility of d-wave pairing in theories of the high- cuprates is briefly discussed.
- Received 29 November 1993
DOI:https://doi.org/10.1103/PhysRevB.49.12318
©1994 American Physical Society