Purcell effect on CdSe/ZnSe quantum dots em bedded in pillar microcavities

We present results on two approaches for placing II‐VI quantum dots in resonance with a pillar microcavity. The first approach consists in growing a fully epitaxial structure: a ZnTe 3λ/2 cavity containing CdTe quantum dots sandwiched between two CdMgTe/CdZnMgTe distributed Bragg reflectors. We observed a strong enhancement of the emission intensity for a dot well located into a 0.9 µm diameter pillars. More striking results were obtained using CdSe QDs in a λ/2 ZnSe cavity sandwiched between SiO2/TiO2 Bragg reflectors. We probed the Purcell effect by time‐resolved photoluminescence and intensity saturation measurements performed on single quantum dots located in a 1.1 µm diameter hybrid pillar. A four‐fold enhancement of quantum dot spontaneous emission rate is observed for quantum dots in resonance with excited degenerated modes of the pillar. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)