Optical properties of high-frequency Au gratings with a fixed period (296.6 ± 0.5 nm) and a variable modulation depth are studied using measurements of spectral and angular dependence of transmission and reflection of polarized light in order to build the dispersion curves of excited optical modes and to identify their types.
View Article and Find Full Text PDFSilica-coated gold (Au) nanoparticles were prepared and their morphological and X-ray absorption properties were investigated. These core-shell type nanoparticles are very stable in aqueous media and may be suitable for an X-ray contrast agent in biological systems. Transmission electron micrographs confirmed well-separated and relatively homogeneous morphology of the nanoparticles in highly concentrated colloids.
View Article and Find Full Text PDFNanoparticles under a few nanometres in size have structures and material functions that differ from the bulk because of their distinct geometrical shapes and strong quantum confinement. These qualities could lead to unique device applications. Our mass spectral analysis of CdSe nanoparticles reveals that (CdSe)(33) and (CdSe)(34) are extremely stable: with a simple solution method, they grow in preference to any other chemical compositions to produce macroscopic quantities.
View Article and Find Full Text PDF