Nonmonotonic Dependence of the Photoluminescence Peak Position of Cadmium Selenide Nanocrystals as a Function of the Excitation Photon Energy

The photoluminescence properties of colloidal CdSe quantum dots with a mean size of 3 nm were studied. The experimental results revealed the nonmonotonic dependence of the photoluminescence peak’s position as a function of the excitation photon energy being varied from 2.41 to 3.68 eV. This effect can be explained by the size distribution of the nanocrystals and the spectral dependence of their absorption coefficients.