Ab Initio Modeling of Thermal Transport through van der Waals Materials

TL;DR

This paper introduces an ab initio modeling approach to understand and engineer thermal transport in van der Waals materials composed of layered transition metal dichalcogenides, revealing microscopic vibrational transfer mechanisms.

Contribution

It presents a first-principles based method to analyze phonon transport in vdWMs with partial overlaps, enabling nanoscale heat flow engineering.

Findings

Vibrations transfer microscopically along the overlap region.

Overlap acts as a filter for phonon states.

Heat flow can be engineered by selecting TMD monolayers.

Abstract

An advanced modeling approach is presented to shed light on the thermal transport properties of van der Waals materials (vdWMs) composed of single-layer transition metal dichalcogenides (TMDs) stacked on top of each other with a total or partial overlap only in the middle region. It relies on the calculation of dynamical matrices from first-principle and on their usage in a phonon quantum transport simulator. We observe that vibrations are transferred microscopically from one layer to the other along the overlap region which acts as a filter selecting out the states that can pass through it. Our work emphasizes the possibility of engineering heat flows at the nanoscale by carefully selecting the TMD monolayers that compose vdWMs.