Diagrammatic Quantum Monte Carlo solution of the two-dimensional Cooperon-Fermion model

TL;DR

This paper introduces a new quantum Monte Carlo method to study a 2D cooperon-fermion model, revealing insights into transition temperature, band gap, cooperon mass, and diamagnetism, with implications for high-$T_{c}$ cuprates.

Contribution

A novel continuous-time diagrammatic determinant quantum Monte Carlo algorithm applied to the 2D cooperon-fermion model, providing new insights into its properties and diamagnetism.

Findings

Estimated the transition temperature $T_c$.

Found delocalization of cooperons enhances diamagnetism.

Results qualitatively agree with experimental measurements in cuprates.

Abstract

We investigate the two-dimensional cooperon-fermion model in the correlated regime with a new continuous-time diagrammatic determinant quantum Monte Carlo (DDQMC) algorithm. We estimate the transition temperature $T_{c}$, examine the effectively reduced band gap and cooperon mass, and find that delocalization of the cooperons enhances the diamagnetism. When applied to diamagnetism of the pseudogap phase in high-$T_{c}$ cuprates, we obtain results in a qualitative agreement with recent torque magnetization measurements.