摘要
Single,free-standing GaN nanowires grown by plasma-assisted molecular-beam epitaxy have been investigated with low temperature micro-photoluminescence.The quantitative analysis of the luminescence spectra of around 100 nanowires revealed that each nanowire exhibits its own individual spectrum.A significant fraction of nanowires exclusively emits at energies corresponding to either surface-donor-bound or free excitons,demonstrating that optical properties of individual nanowires are determined by a few impurity atoms alone.The number of impurities per nanowire and their location within the nanowires varies according to Poissonian statistics.
基金
This work was partially supported by the EU Marie Curie RTN contract MRTN-CT-2004-005583(PARSEM)and by the IST project NODE 015783.
