Exact Solution of a Electron System Combining Two Different t-J Models

TL;DR

This paper introduces an exactly solvable electron model combining two types of sites with different occupancy rules, solved via a modified algebraic Bethe Ansatz, revealing detailed ground and excited state properties.

Contribution

It presents a novel strongly correlated electron model with mixed site types and provides an exact solution using a modified algebraic Bethe Ansatz.

Findings

Exact solutions for ground and excited states in the thermodynamic limit.

Model treats impurity-like site variations as a new parameter.

Demonstrates the integrability of a complex mixed-site electron system.

Abstract

A new strongly correlated electron model is presented. This is formed by two types of sites: one where double occupancy is forbidden, as in the t-J model, and the other where double occupancy is allowed but vacancy is not allowed, as an inverse t-J model. The Hamiltonian shows nearest and next-to-nearest neighbour interactions and it is solved by means of a modified algebraic nested Bethe Ansatz. The number of sites where vacancy is not allowed, may be treated as a new parameter if the model is looked at as a t-J model with impurities. The ground and excited states are described in the thermodynamic limit.