title: Strain dependence of the heat transport properties of graphene nanoribbons.
abstract: Using a combination of accurate density-functional theory and a nonequilibrium Green's function method, we calculate the ballistic thermal conductance characteristics of tensile-strained armchair (AGNR) and zigzag (ZGNR) edge graphene nanoribbons, with widths between 3 and 50 Å. The optimized lateral lattice constants for AGNRs of different widths display a three-family behavior when the ribbons are grouped according to N modulo 3, where N represents the number of carbon atoms across the width of the ribbon. Two lowest-frequency out-of-plane acoustic modes play a decisive role in increasing the thermal conductance of AGNR-N at low temperatures. At high temperatures the effect of tensile strain is to reduce the thermal conductance of AGNR-N and ZGNR-N. These results could be explained by the changes in force constants in the in-plane and out-of-plane directions with the application of strain. This fundamental atomistic understanding of the heat transport in graphene nanoribbons paves a way to effect changes in their thermal properties via strain at various temperatures.
authors.affiliation: Department of Chemistry, National University of Singapore, Singapore.
authors.forename: Pei Shan Emmeline
authors.initials: PS
authors.lastname: Yeo
authors.forename: Kian Ping
authors.initials: KP
authors.lastname: Loh
authors.forename: Chee Kwan
authors.initials: CK
authors.lastname: Gan
mesh_terms: D003198:Computer Simulation; D055119:Elastic Modulus; D004735:Energy Transfer; D006108:Graphite / Q000737:chemistry*; D006358:Hot Temperature; D008956:Models, Chemical; D008958:Models, Molecular; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D013814:Thermal Conductivity
chemical_list: D006108:Graphite