Recombination Dynamics in Nitride Quantum Boxes and Quantum Wells for Colors Ranging from the UV to the Red

Abstract

ABSTRACTTime-resolved photoluminescence experiments at varying temperature are performed on a series of InxGa1−xN/GaN quantum well and quantum box samples of similar compositions (0.15 < x < 0.20). The results are analyzed by using envelope-function calculations of transition energies and oscillator strengths, accounting for internal electric fields. The respective influences of localization and electric fields on radiative and nonradiative lifetimes and on the Stokes shift are deduced. The results indicate that the spatial extension of localization centers is much smaller than the size of the quantum boxes (∼10 × 3 nm, typically). The room-temperature radiative efficiency of both quantum well and quantum box samples is enhanced by replacing the topmost GaN barrier by an AlGaN one.