Alloy-like behaviour of the thermal conductivity of non-symmetric superlattices

TL;DR

This paper introduces an alloy-like phenomenological model to describe the thermal conductivity of non-symmetric superlattices, extending the Norbury rule to crystalline systems and highlighting the influence of interface resistance.

Contribution

It generalizes the Norbury rule to non-symmetric superlattices, providing a new approach to estimate thermal conductivity and interface resistance in complex layered materials.

Findings

The model fits the thermal conductivity data of non-symmetric superlattices.

Interface thermal resistance depends on superlattice period and material ratio.

The approach has potential applications in designing materials with tailored thermal properties.

Abstract

In this work, we show a phenomenological alloy-like fit of the thermal conductivity of (A)d1:(B)d2 superlattices with d1 /= d2, i.e. non-symmetric structure. The presented method is a generalization of the Norbury rule of the summation of thermal resistivities in alloy compounds. Namely, we show that this approach can be also extended to describe the thermal properties of crystalline and ordered-system composed by two or more elements, and, has a potentially much wider application range. Using this approximation we estimate that the interface thermal resistance depends on the period and the ratio of materials that form the superlattice structure