Supersymmetric Mean-Field Theory of t-J Model

TL;DR

This paper develops a supersymmetric mean-field theory for the t-J model, revealing stable phases and excitation branches, and refines phase transition points with Gutzwiller's method.

Contribution

It introduces a supersymmetric formulation of the t-J model at the mean-field level, identifying phase stability and new excitations, and improves transition doping estimates.

Findings

Slave-fermion-like spiral phase stable at low doping

Slave-boson-like d-wave pairing favored at doping ≥ 0.23

Gutzwiller's method lowers transition doping to 0.06

Abstract

The supersymmetric formulation of t-J model is studied in this paper at the mean-field level where $\delta$-T phase diagram is computed. We find that slave-fermion-like spiral phase is stable at low doping concentration, and the slave-boson-like d-wave fermionic spin pairing state becomes energetically favourable when $\delta\geq$ 0.23. An improvement in free energy using Gutzwiller's method lowers the transition doping concentration to 0.06. We also point out the existence of new branches of excitations in the supersymmetric theory.