Controlling thermal conductivity in harmonic chains with correlated mass and bond disorder: Analytical approach

TL;DR

This paper analytically studies heat transport in one-dimensional harmonic chains with correlated mass and bond disorder, showing how tuning correlations can control the scaling of thermal conductivity for potential thermoelectric and insulation applications.

Contribution

It provides an analytical framework demonstrating that the scaling of thermal conductivity depends solely on either mass or bond disorder, not their cross-correlations.

Findings

Thermal conductivity scaling is determined by either mass or bond disorder.

Cross-correlations between disorders do not affect the scaling behavior.

Tuning self-correlations allows control over thermal conductivity scaling.

Abstract

We investigate heat transport in one-dimensional harmonic chains with mass disorder and weak bond disorder, coupled at both ends to oscillator heat baths through weak impedance mismatches. The model incorporates correlations in mass disorder, in bond disorder, and between the two. We find that the scaling of thermal conductivity $\kappa$ with system size $N$ is determined solely by either mass disorder or bond disorder. This indicates that cross-correlations between the two types of disorder play no important role in the scaling behavior of $\kappa$. Consequently, by tuning the self-correlations, it is possible to control how the thermal conductivity scales with the system size. Such control could have potential applications in thermoelectric devices and thermal insulation technologies.