Localized exciton and its stimulated emission in surface mode from single-layerInxGa1xN

Abstract
Exciton localization in InxGa1xN was studied. At 2 K, the time-integrated photoluminescence (PL) spectrum showed a Stokes shift from the absorption shoulder and broadening at the lower photon energy side. Site-selectively excited PL measurements determined the mobility edge. The exciton relaxation processes were studied by use of time-resolved PL spectroscopy. The PL decay time increased with the decrease of the detection-photon energy, indicating the dynamical features of exciton localization. In addition, we observed localized exciton luminescence turned into stimulated emission just below the mobility edge.