Suppression of Blinking and Enhancement of Optical Properties of Core-Shell Quantum Dots by Structural Formulation

Abstract

Core-shell quantum dots (QDs) have gained immense significance in various technological applications due to their unique size-dependent optical properties. However, their efficiency in lightning and display applications can be limited by fluorescence intermittency or blinking which limits the viability of the QDs. In this work, a theoretical study on the causes and mitigation process of the blinking phenomenon in core-shell QDs has been carried out. An approach to eliminate blinking behavior is to modify the traditional core-shell structure where the interface between the core and shell materials is discontinuous and abrupt. A graded alloy core-shell QD where there is a gradual transition between pure core material and pure shell material shows suppressed blinking behavior. Another alternate strategy is the growth of core-shell QDs with giant shell structures and appropriate surrounding matrix considering the traps being few nanometers away from the core. The study of the effect of fluctuations in the local environment of the QDs helps in understanding the mechanisms of blinking and hence in curtailing its effect. These approaches have been applied and analyzed to suppress the blinking phenomenon and improve the optical properties of QDs.