Large size two-hole bound states in t-J model

TL;DR

This paper reports the discovery of large two-hole bound states in the 2D t-J model, with energies exponentially related to coupling strength, and discusses their potential role in superconductivity.

Contribution

It introduces new large-size two-hole bound states in the t-J model with unique parity properties and exponential energy dependence, advancing understanding of pairing mechanisms.

Findings

Large two-hole bound states are found in the t-J model.

Binding energies depend exponentially on inverse coupling.

States may influence superconducting pairing.

Abstract

Several series of shallow large-size ($l \gg lattice~ spacing$) two-hole bound states are found in the two-dimensional t-J model. Their binding energies depend exponentially on the inverse value of the hole-spin-wave coupling constant. Their parity is connected with the angular wave function in a nonstandard way. The possible role of these states in the formation of superconducting pairing is considered.