Controlling Densities Of Manganese Ions And Cadmium Vacancies In Cd1-Xmnxte Ultrasmall Quantum Dots In A Glass Matrix: X-Concentration And Thermal Annealing

In this work, we used nominal concentration (x) and thermal annealing to control the density of manganese (Mn2+) ions and cadmium vacancies (V-Cds) in Cd1-xMnxTe ultrasmall quantum dots (USQDs) embedded in a glass matrix.. The physical properties were investigated by photoluminescence (PL) and electron paramagnetic reSonance (PPR). PL bands related to surface defects and Mn2 ions intensified, whereas bands related to Vcds decreased with increasing. manganese concentration. Longer thermal annealing times caused decreases in the intensity Of PL bands characteristic of Mn2+ ions and V-Cds. The EPR spectra confirmed that manganese exhibited +2 oxidation states and was incorporated at the core and surface of the Cd1-xMnxTe USQDs. Furthermore, the quantities of Mn2+ ion within the Cd1-xMnxTeTe USQDs confirmed that longer thermal annealing times were associated with constant diffusion of these ions from the core to the surface and then the glass. Therefore, we demonstrated that longer thermal annealing times and higher manganese concentrations make it possible to control both the emissions intensities related to V-Cds and Mn2+ ions and the diffusion of these ions to the surface and then the glass.