Supersymmetry in models with strong on-site Coulomb repulsion - application to t-J model

TL;DR

This paper introduces a supersymmetric framework to enforce the no double occupancy constraint in strongly correlated electron models, unifying and extending slave-boson and slave-fermion methods, with application to the t-J model.

Contribution

A novel supersymmetric formulation for constrained models that unifies slave-boson and slave-fermion approaches and provides new insights beyond traditional methods.

Findings

Incorporates both slave-boson and slave-fermion formulations naturally.

Provides results beyond traditional slave approaches.

Applied successfully to the t-J model in mean-field approximation.

Abstract

A supersymmetric way of imposing the constraint of no double occupancy in models with strong on-site Coulomb repulsion is presented in this paper. In this formulation the physical operators in the constrainted Hilbert space are invariant under local unitary transformations mixing boson and fermion representations. As an illustration the formulation is applied to the $t-J$ model. The model is studied in the mean-field level in the J=0 limit where we show how both the slave-boson and slave-fermion formulations are included naturally in the present approach and how further results beyond both approaches are obtained.