Optical conductivity of a quasi-one-dimensional system with fluctuating order

TL;DR

This paper introduces an exact method to compute the optical conductivity in one-dimensional systems with fluctuating order, revealing significant differences from perturbative approaches and highlighting the impact of correlation length.

Contribution

The authors develop a formally exact numerical approach using coupled Fokker-Planck equations to analyze optical conductivity with classical phase fluctuations.

Findings

Results differ significantly from perturbation theory

Optical conductivity strongly depends on correlation length

Method provides accurate predictions for fluctuating order systems

Abstract

We describe a formally exact method to calculate the optical conductivity of a one-dimensional system with fluctuating order. For classical phase fluctuations we explicitly determine the optical conductivity by solving two coupled Fokker-Planck equations numerically. Our results differ considerably from perturbation theory and in contrast to Gaussian order parameter fluctuations show a strong dependence on the correlation length.