Optical spectroscopy on individual CdSe/ZnMnSe quantum dots

Optical single dot studies in wide-band gap diluted magnetic CdSe/ZnMnSe quantum dots have been performed. Due to the sample design, the photoluminescence energy of the quantum dot signal is energetically below the internal ${\mathrm{Mn}}^{\mathrm{2+}}$ transition, resulting in high quantum efficiencies comparable to nonmagnetic CdSe/ZnSe quantum dots. Magnetic-field- and temperature-dependent measurements on individual dots clearly demonstrate the exchange interaction between single excitons and individual ${\mathrm{Mn}}^{\mathrm{2+}}$ ions, resulting in a giant Zeeman effect and a formation of quasi-zero-dimensional magnetic polarons.