Attribution of the 3.45 eV GaN nanowires luminescence to inversion domain boundaries

Using correlated experiments on single nanowires (NWs) by microphotoluminescence (μ-PL) and high resolution scanning transmission electron microscopy, we attribute the 3.45 eV luminescence of GaN NWs grown by plasma assisted molecular beam epitaxy (PA-MBE) to the presence of prismatic inversion domain boundaries (pIDBs). This attribution is further strengthened by a recent publication demonstrating the observation of pIDBs in PA-MBE grown GaN NWs. A statistical study of the presence of 3.45 eV lines in NWs PL spectra allows to estimate the ratio of single NWs nucleating with a pIDB to be 50% in the sample under scrutiny.