Extended bound states and resonances of two fermions on a periodic lattice

Abstract

The high-$T_c$ cuprates are possible candidates for d-wave superconductivity, with the Cooper pair wave function belonging to a non-trivial irreducible representation of the lattice point group. We argue that this d-wave symmetry is related to a special form of the fermionic kinetic energy and does not require any novel pairing mechanism. In this context, we present a detailed study of the bound states and resonances formed by two lattice fermions interacting via a non-retarded potential that is attractive for nearest neighbors but repulsive for other relative positions. In the case of strong binding, a pair formed by fermions on adjacent lattice sites can have a small effective mass, thereby implying a high condensation temperature. For a weakly bound state, a pair with non-trivial symmetry tends to be smaller in size than an s-wave pair. These and other findings are discussed in connection with the properties of high-$T_c$ cuprate superconductors.

21 pages, RevTeX, 4 Postscript figures, arithmetic errors corrected. An abbreviated version (no appendix) appeared in PRB on March 1, 1997

References in corpus (2)

• Antiferromagnetic and van Hove Scenarios for the Cuprates: Taking the Best of Both Worlds
• Superconducting Order Parameter Symmetry in Multi-layer Cuprates

Cited by in corpus (5)

• Developments in the negative-U modelling of the cuprate HTSC systems
• The pseudogap in underdoped high Tc superconductors in the framework of the Boson Fermion model
• Non-Fermi liquid scattering against an emergent Bose liquid: manifestations in the kink and other exotic quasiparticle behaviors in the normal-state cuprate superconductors
• Bound states in the phase diagram of the extended Hubbard model
• Real-space d-wave superconductivity from weak attraction