Manipulation of heat current by the interface between graphene and white graphene

TL;DR

This study explores how the shape and length of interfaces between graphene and white graphene influence heat transfer, revealing that zigzag interfaces significantly reduce heat flow due to localized phonon modes.

Contribution

It provides a combined molecular dynamics and Green's function analysis of interface shape effects on heat transfer in graphene-based materials, highlighting the role of localized phonon modes.

Findings

Heat current decreases linearly with interface length.

Zigzag interfaces cause stronger heat reduction than armchair interfaces.

Room temperature thermal resistance varies with interface shape.

Abstract

We investigate the heat current flowing across the interface between graphene and hexagonal boron nitride (so-called white graphene) using both molecular dynamics simulation and nonequilibrium Green's function approaches. These two distinct methods discover the same phenomena that the heat current is reduced linearly with increasing interface length, and the zigzag interface causes stronger reduction of heat current than the armchair interface. These phenomena are interpreted by both the lattice dynamics analysis and the transmission function explanation, which both reveal that the localized phonon modes at interfaces are responsible for the heat management. The room temperature interface thermal resistance is about $7\times10^{-10}$m$^{2}$K/W in zigzag interface and $3.5\times10^{-10}$m$^{2}$K/W in armchair interface, which directly results in stronger heat reduction in zigzag interface. Our theoretical results provide a specific route for experimentalists to control the heat transport in the graphene and hexagonal boron nitride compound through shaping the interface between these two materials.