ABSTRACT
This chapter develops the main ideas of the heat transport in the nanoscale. It explains the physical phenomena change considerably when we pass from the bulk materials to the nanostructured materials or nanostructures. The ratio interfaces- surfaces/total volume increases and the phonon mean free path (PMFP) becomes at the same order as the characteristic sizes of the nanostructures. Nanostructuration may be viewed as a way to tune the thermal transport properties of a material, as compared with the thermal conductivity characterizing the bulk state. Typically nanostructuration is a way to reduce the phononic thermal conductivity of a bulk material. This reduction is realized because of the large density of interfaces present in the nanostructured materials, which strongly scatter the energy carriers thus contributing to deteriorate energy transport at least in the direction perpendicular to the interfaces.
