The dynamics of quasi zero-dimensional excitons and biexcitons in a single quantum dot has been studied by time-resolved photoluminescence spectroscopy. The monoexponential decay of the biexciton and the plateau-like behaviour of the exciton transient, are well described by a statistical treatment of the dynamics, i.e. by taking into accout the discrete number of excitons allowed in the ground state of the quantum dot. Surprisingly, the radiative recombination lifetime of the biexciton is found to be comparable to the exciton one. Model calculations demonstrate that this remarkable result is a consequence of the spin structure of the recombining particles and the spatial separation of the holes in a quantum dot of finite extension.
|Number of pages||5|
|Journal||Physica Status Solidi (B) Basic Research|
|Publication status||Published - Sep 2000|