Diameter dependence of the wurtzite-zinc blende transition in inas nanowires

We demonstrate that the crystal structure of InAs nanowires can be controlled with nanowire diameter and growth temperature. At small diameters, the nanowires exhibit a wurtzite structure. As the diameter is increased, there is a crossover to the zinc blende structure. The crossover is less sharp at lower growth temperature and the crossover diameter decreases as the growth temperature is increased. We explain these results with classical nucleation theory. The strong diameter dependence is accounted for by including the Gibbs-Thomson effect in the chemical potential.