title: Lattice thermal conductivity crossovers in semiconductor nanowires.
abstract: For binary compound semiconductor nanowires, we find a striking relationship between the nanowire's thermal conductivity kappa(nwire), the bulk material's thermal conductivity kappa(bulk), and the mass ratio of the material's constituent atoms, r, as kappa(bulk)/kappa(nwire) (alpha) (1+1/r)(-3/2). A significant consequence is the presence of crossovers in which a material with higher bulk thermal conductivity than the rest is no longer the best nanowire thermal conductor. We show that this behavior stems from a change in the dominant phonon scattering mechanism with decreasing nanowire size. The results have important implications for nanoscale heat dissipation, thermoelectricity, and thermal conductivity of nanocomposites.
authors.affiliation: NASA-Ames Center for Nanotechnology, 229-1, Moffett Field, CA 94035, USA.
authors.forename: N
authors.initials: N
authors.lastname: Mingo
authors.forename: D A
authors.initials: DA
authors.lastname: Broido