Intersubband optical transitions, refractive index changes, and absorption coefficients are numerically driven for direct bandgap strained GeSn/Ge quantum dots. The linear, third-order nonlinear and total, absorption coefficients and refractive index changes are evaluated over useful dot sizes’ range ensuring p-like Γ-electron energy state to be lower than s-like L-electron energy state. The results show strong dependence of the total absorption coefficient and refractive index changes on the quantum dot sizes. The third order nonlinear contribution is found to be sensitive to the incident light intensity affecting both total absorption coefficient and refractive index changes, especially for larger dot sizes.
This work investigates the antibacterial potential of TiO2‐based glass‐ceramic. A glass of TiO2 microcrystals embedded in glass matrix of BaO‐TiO2‐B2O3was obtained by melt quench method followed by controlled heat treatment at the 650°C for 3 hours. Crystallization of anatase phase of TiO2 was confirmed by X‐ray diffraction. UV‐visible absorbance and photoluminescence were also recorded. Interestingly band gap of TiO2 glass‐ceramic (crystallized glass) was found to be 2.9 eV. Crystallized glass showed excellent antibacterial property against Escherichia coli in both forms (powder and plate). More than 90% of disinfection was achieved by photocatalytic TiO2 glass‐ceramic surface within one hour of sunlight exposure, which was significantly higher than as‐quenched glass surface and TiO2 glass‐ceramic surface under dark. Intracellular reactive oxygen species (ROS) intensity of bacterial cells in the presence of crystallized glass was almost three times higher than the control and as‐quenched glass under light. Higher production of ROS is major factor for bacterial degradation on crystallized glass surface.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.