On the Internal Structure of the Singlet d$_{X^2-Y^2}$ Hole Pair in an Antiferromagnet

TL;DR

This paper investigates the internal structure of singlet d_{x^2-y^2} hole pairs in antiferromagnets using exact diagonalizations, revealing dominant correlations at next-nearest neighbor distances and proposing a new pair operator to describe their spatial extension.

Contribution

It introduces a novel form of the singlet d_{x^2-y^2} pair operator to better describe the spatial structure of hole pairs in antiferromagnetic systems.

Findings

Dominant hole-hole correlations at next-nearest neighbor distances.

Proposal of a new pair operator capturing the pair's spatial extension.

Insights into the internal structure of hole pairs in antiferromagnets.

Abstract

Exact diagonalizations of two dimensional small t--J clusters reveal dominant hole-hole correlations at distance $\sqrt{2}$ (ie between holes on next nearest neighbor sites). A new form of singlet $d_{x^2-y^2}$ pair operator is proposed to account for the spatial extention of the two hole-bound pair beyond nearest neighbor sites.