III-V semiconductor nanowires for optoelectronic device applications

III-V semiconductor nanowires are promising candidates for optoelectronic device applications due to their unique one dimensional geometry. High quantum efficiency, defined as QE=τ_nr/(τ_nr+τ_r), where τ_nr is the non-radiative lifetime and τ_r is the radiative lifetime of minority carriers in the nanowires is necessary for device applications. Due to the large surface area to volume ratio in the nanowires, non-radiative recombination associated with surface states often results in low quantum efficiency. The quantum efficiency of the nanowires can be increased either by increasing τ_nr or by reducing τ_r. We present experimental results on these two different approaches to increase the quantum efficiency of semiconductor nanowires.