Molecular Dynamics Modeling of Thermal Conductivity of Silicon/Germanium Nanowires

The thermal conductivity of silicon/germanium nanowires with different geometry and composition has beenstudied by using the nonequilibrium molecular dynamics method. The thermal conductivity of the Si1-xGexnanowire is shown to firstly decrease, reaches a minimum at x=0.4 and then to increase, as the germaniumcontent x grows. It was found that in the tubular Si nanowires the thermal conductivity decreases monotonouslywith increasing radius of the cylindrical void. The phonon spectra were calculated and the mechanisms of phononscattering in the investigated nanowires were analyzed.