Growth and magneto-optical properties of CdSe/ZnMnSe self-assembled quantum dots

We have investigated evolution of CdSe self-assembled quantum dots (QDs) grown on ZnMnSe diluted magnetic semiconductor (DMSs). In a series of QD systems, CdSe coverage was varied from 1.5 to 2.5 ML while constant Mn concentration was kept in the ZnMnSe barrier. The PL peak from CdSe QDs shows systematic red shift with increasing CdSe coverage. This behavior observed in the series of CdSe/ZnMnSe QDs systems indicates systematic evolution of CdSe QD with increasing CdSe coverage. The PL peaks from CdSe QDs and from ZnMnSe barrier show large Zeeman shift, which is a characteristic of DMS systems when a magnetic field is applied. From the ratio of the Zeeman shift observed from CdSe QDs to that observed from ZnMnSe barrier, we are able to extract degree of carrier wave function penetration into the ZnMnSe barrier, which turns out to be systematically decreased with increasing CdSe coverage.