Optical investigation of CdSe/Zn(Be)Se quantum dot structures: size and Cd composition
نویسندگان
چکیده
The optical properties of CdSe/Zn0.97Be0.03Se and CdSe/ZnSe quantum dots (QDs) are investigated using photoluminescence (PL) and PL excitation spectroscopies. We show that the addition of Be into the barrier enhances the Cd composition and the overall quantum confinement of optically active QDs. The temperature behavior of PL supports such a conclusion. We also show that the room temperature QD PL exhibits a supra-linear dependence on the excitation intensity, which is attributed to the recombination involving relatively strongly localized holes and quasi-free electrons.
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