Magneto-photoluminescence studies of CdTe/CdSe/ZnS nanoparticles

Recently, the effect of the magnetic flux on the excitonic energy has received much attention. Optical Aharonov-Bohm was observed on negatively charged exciton in InGaAs/GaAs quantum ring as well as neutral exciton in type-II InP-GaAs heterostrcture. In this talk we'll present our magneto-photoluminescence studies on the optical properties of CdTe/CdSe/ZnS system. The nanoparticles that were grown by chemical method have size of about 6 nm and the band alignment between the core (CdTe) and the shell (CdSe) is a type--II band alignment. The addition of ZnS layer is to passivate the surface of CdSe and to enhance the light emitting efficiency. Magneto-photoluminescence experiment was performed at T=1.4 K with a 14 T superconducting magnet in conjunction with a green diode laser and a monochromator. Oscillation on the peak energy of the photoluminescence spectra as well as oscillation in the integrated intensity as a function of magnetic field were observed and are attributed to the optical Aharonov-Bohm-like effect.