Temporal profiles of excitons in surface‐modified CdS and CdMnS quantum dots prepared by a reverse‐micelle method

We have investigated surface-modification effects on photoluminescence properties of CdS and CdMnS quantum dots (QDs) prepared by a reverse-micelle method from the viewpoint of photoluminescence dynamics. By the surface modification, the band-edge luminescence intensity is markedly increased in CdS QDs. The surface modification also causes drastic changes of decay profiles of the band-edge luminescence. The Mn2+ luminescence originated from the intra-3d shell transition of Mn2+ is clearly observed in CdMnS QDs, and its intensity is also increased by the surface modification. Furthermore, the decay time of the band-edge luminescence in surface-modified CdMnS QDs is faster than that in CdS QDs, which is due to the energy transfer from excitons to Mn2+. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)