Dimension dependence of negative differential thermal resistance in graphene nanoribbons

TL;DR

This study explores how the negative differential thermal resistance (NDTR) phenomenon in graphene nanoribbons varies with their dimensionality, width, and layering, revealing conditions under which NDTR appears or disappears.

Contribution

It provides a comprehensive analysis of the dimension-dependent behavior of NDTR in GNRs using molecular dynamics simulations, highlighting the effects of width, layers, and length.

Findings

NDTR appears in wider, two-dimensional GNRs.

NDTR diminishes and disappears as GNRs become three-dimensional.

NDTR vanishes in the thermodynamic limit with increasing length.

Abstract

Negative differential thermal resistance (NDTR) in approximate graphene nanoribbons (GNRs) is investigated from one dimension to three dimensions by using classical molecular dynamics method. For single-layer GNRs, NDTR can not be observed for very narrow GNRs (one dimension), NDTR appears when the width of GNRs increases (two dimensions). However, NDTR disappears gradually on further increasing the width. For multiple-layer GNRs, when the number of the layers increases, GNRs becomes from two-dimensional system to three-dimensional system, NDTR regime reduces and eventually disappears. In addition, when the length of GNRs increases, NDTR regime also reduces and vanishes in the thermodynamic limit. These effects may be useful for designing thermal devices where NDTR plays an important role.