Morphological stability of a nanowire during growth process

In this letter, we analyze the morphological stability of a nanowire during the vapor-solid (VS) side growth process at the same time as it grows along its axial direction by the vapor-liquid-solid (VLS) mechanism. The longitudinal perturbations due to the fluctuations of the growth conditions are introduced to describe the morphological variance of a nanowire along its fibre direction. It is shown that the side growth can induce the morphological instability for a nanowire with side perturbations if the perturbation's wavelengths are larger than a nanowire's perimeter.