Carrier redistribution between different potential sites in semipolar (20(2)over-bar1) InGaN quantum wells studied by near-field photoluminescence

Scanning near-field photoluminescence (PL) spectroscopy at different excitation powers was applied to study nanoscale properties of carrier localization and recombination in semipolar (20 (2) over bar1) InGaN quantum wells (QWs) emitting in violet, blue, and green-yellow spectral regions. With increased excitation power, an untypical PL peak energy shift to lower energies was observed. The shift was attributed to carrier density dependent carrier redistribution between nm-scale sites of different potentials, Near-field PL scans showed that in (20 (2) over bar1) QWs the in-plane carrier diffusion is modest, and the recombination properties arc uniform, which is advantageous for photonic applications.