Polaron in the t-J Models with Three-Site Terms: the SU(2) and the Ising Cases

TL;DR

This paper compares the impact of three-site terms on polaron behavior in t-J models with SU(2) and Ising symmetries, highlighting their differing significance in low doping regimes.

Contribution

It demonstrates that three-site terms are crucial for polaron dynamics in the Ising t-J model but less so in the SU(2) case.

Findings

Three-site terms significantly affect polaron movement in the Ising model.

In the SU(2) model, three-site terms have a negligible effect.

The role of three-site terms varies with the symmetry of the t-J model.

Abstract

We compare the role of the three-site terms added to the t-J models in the SU(2) and the Ising cases in the extremely low doping regime, i.e. when a single hole added to the strongly interacting half-filled system becomes a polaron. We show that in the realistic Ising case the three-site terms play a vital role in the polaron movement and should never be neglected unlike in the SU(2) case.