Nanowires have fascinating electronic and mechanical properties due to their two-dimensional character with huge industrial applicability potential. Their diameter is typically below 100 nm, and they posses a large aspect ratio between length and radius of more than 100, exhibiting one dimensional properties e.g. in quantization of the electrocis states. Nanowires belong to the best controllable structures on the nanoscale. Potential applications are field effect transistors, p-n diods, LEDs, nanolaser, complex logical gates, gas sensors, nanoresonators, etc.. Since their properties can be well controlled during fabrication, they can be designed with specific electronic properties.
From a technological point of view, he mechanical stability of the wires on long timescales is essential. As a general fact, cylindrical objects suffer from an instability towards a decomposition into droplets, driven by isotropic surface energy. This instability has been predicted by Rayleigh and Plateau, and has been investigated by Nichols and Mullins. It can play a substantial effect also in nanowires. This predicts that sufficiently long wires will always decompose into droplets. The growth rate for such an instability reaches a maximum for a specific wavelength of the perturbation, which depends on the transport mechanism, like surface diffusion. There are experimental observations for the decomposition of gold nanowires at temperatues below 500 C. Due to the low temperatures where this degradation process can occur, it has to considered for the production and use of nanomaterials. On the other hand, such natural instabilities may be used on purpose for applications in optical conductors.