Laser-induced Precipitation of Cd1-xZnxSe Graded Quantum Dots in Silicate Glasses

Abstract

Quantum dots(QDs) have been studied extensively for LED color converters, bio-imaging sensors and photocatalyst utilizing the high quantum efficiencies of QDs. However, intrinsic emission from the single QD suffers low intensities mainly due to surface defects. Although Cd1-xZnxSe graded structure have been realized by conventional, it has been difficult to control the spatial distribution of QDs in glasses. We fabricated silicate glasses with high Se/Cd ratios and precipitated Ag nanoparticles in the glasses using ion exchange method. Then, 532 nm continuous-wave laser was irradiated onto the glass surface to precipitate Cd1xZnxSe graded QDs. It was found that photoluminescence (PL) from the surface defects of QDs significantly decreased. Compositions and morphologies of QDs are being analyzed.