Staircase-like spectral dependence of ground-state luminescence time constants in high-density InAs/GaAs quantum dots

Time-resolved photoluminescence (PL) from InAs/GaAs quantum dots with a bim odal size distribution is used to investigate the dynamic carrier-transfer processes which couple transfer between similarly sized quantum dots and be tween quantum dots in different size categories. The relationship between t he decay time and the emission energy appears staircaselike and the energet ic positions of the steps as well as the shape can be correlated to the sha pe of the steady-state PL emission through a rate-equation theory. These re sults show how transient PL can be used to investigate the dynamics of carr ier transfer in quantum-dot systems. (C) 2001 American Institute of Physics .