Ultrafast Exciton Trapping Dynamics in ZnSe/(CdSe)_m (ZnSe))_n Short Period Superlattice Quantum Wells

The ultrafast exciton trapping dynamics in ZnSe/ZnCdSe short period superlattice quantum wells has been studied by using transient photoluminescence spectroscopy. A rapid exciton trapping time of less than 7ps from the barriers to the wells is measured. In Te doped samples self-trapped excitons give rise to Stokes shifted broad band luminescence and exhibit much longer lifetime.