Limits on Phase Separation for Two-Dimensional Strongly Correlated Electrons

TL;DR

This study uses high-temperature series calculations to analyze phase separation in the two-dimensional t-J model, confirming it occurs only above a certain J/t ratio and identifying the critical temperature for the phase transition.

Contribution

The paper introduces a novel method of using series ratios of free energy per hole to accurately investigate phase separation in the 2D t-J model.

Findings

Phase separation occurs only for J/t > 1.2.

Critical temperature for phase transition is approximately 0.25J.

Series extrapolation provides precise insights into low-temperature behavior.

Abstract

From calculations of the high temperature series for the free energy of the two-dimensional t-J model we construct series for ratios of the free energy per hole. The ratios can be extrapolated very accurately to low temperatures and used to investigate phase separation. Our results confirm that phase separation occurs only for J/t greater than 1.2. Also, the phase transition into the phase separated state has Tc of approximately 0.25J for large J/t.