Luttinger Liquid Instability in the One Dimensional t-J Model

TL;DR

This paper investigates the one-dimensional t-J model, revealing a Luttinger liquid phase across most parameters and discovering a new Luther-Emery phase with superconducting correlations at low densities and high interaction strengths.

Contribution

It introduces a numerical projection method from a Luttinger liquid trial wave function and identifies a novel Luther-Emery phase in the t-J model.

Findings

Luttinger liquid behavior dominates most of the phase diagram.

A new Luther-Emery phase with a spin gap and enhanced superconductivity is found at low densities.

The Luther-Emery phase exhibits distinct correlation functions.

Abstract

We study the t-J model in one dimension by numerically projecting the true ground state from a Luttinger liquid trial wave function. We find the model exhibits Luttinger liquid behavior for most of the phase diagram in which interaction strength and density are varied. However at small densities and high interaction strengths a new phase with a gap to spin excitations and enhanced superconducting correlations is found. We show this phase is a Luther-Emery liquid and study its correlation functions.