Phonon thermal conductance calculations were performed, for silicon nanowires having diameters ranging from 1 to 5nm, by using non-equilibrium Green's function technique involving the interatomic Tersoff potential. It was found that the introduction of the defects reduced the thermal conductance significantly and that a so-called center-defect reduced thermal conductance much more than a so-called surface defect. It was also found that the thermal conductance changed its behaviour from the usual ohmic-type at room temperature, proportional to its cross-sectional area, to the unusual quantum-type at low temperature, not dependent on the cross-sectional area. The temperature for the crossover to quantized thermal conductance was found around at 100K.

Effects of Vacancy Defects on Thermal Conduction of Silicon Nanowire: Nonequilibrium Green's Function Approach. K.Yamamoto, H.Ishii, N.Kobayashi, K.Hirose: Applied Physics Express, 2011, 4[8], 085001