OPTICAL-PROPERTIES OF MANGANESE-DOPED ZNSE ZNS QUANTUM DOTS GROWN BY MOLECULAR-BEAM EPITAXY/

Optical properties of Mn-doped ZnSe/ZnS quantum dots (QD's) have been investigated by both steady-state and time-resolved photoluminescence (PL) measurements. Strong photoluminescence associated with Mn intra-d shell transitions has been observed for QD's with a longitudinal thic kness of just few monolayers (ML's). The PL decay involves two process es with different lifetimes of which the faster one has a lifetime of about 5 mu s which is almost independent of the well thickness, while the other process has a Lifetime varying from 40 to 80 mu s when the w ell width decreases from 6 to 0.25 ML. The experimental results are in terpreted by the use of rate equations which suggests that the enhance d Mn emission might be due to the relatively enhanced energy transfer from the QD's to the Mn atoms.