Efficient Gamma Ray Detection Using CdTe/CdS Core/Shell Quantum Dots: A Simple and Rapid Fluorescence Approach.

Gamma rays, as hazardous nuclear radiation, necessitate effective and rapid detection methods. This paper introduces a low-cost, fast, and simple fluorescence method based on CdTe/CdS core/shell quantum dots for gamma-ray detection. CdTe/CdS quantum dots, subjected to gamma irradiation from a Co source under various conditions, were investigated to assess their fluorescence sensor capabilities.

Low-threshold bistability in nonlinear microring tower resonator.

Microring tower resonators, which are a chain of microring resonators stacked on top of each other, are of great interest for nonlinear optics due to their unique features such as very high compactness, coupling efficiency and quality factor. In this research, we investigate the optical bistability in microring tower (MRT) with Kerr nonlinearity by using the coupled mode theory, and demonstrate how a proper defect into the structure can lead to low threshold bistability. In particular, we observed optical bistability in nonlinear defect modes with switching power as low as 165 μW through numerical calculations in a structure with a overall loss on the order of 0.

Linear transmission properties of a vertically stacked multiring resonator with a defect.

The linear characteristics of a vertically stacked multiring resonator (VMR) that can support a photonic bandgap with a defect located at the middle of the structure are investigated numerically. Initially, the spectral transfer characteristics of the uniform structure are studied. Then, the transmission properties of the VMR structure possessing a defect are investigated.