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Reports on the growth of Cd[sub x]Zn[sub 1-x]Te epilayers on gallium arsenide (GaAs) substrates by molecular beam epitaxy. Study of the optical properties of the epilayers by taking reflectance and photoluminescence measurements; Energy gaps of the epilayers which decrease as the Cd content increases.

Abstract: We report the characterization of nano-size zinc oxide (ZnO) powder synthesized via microwave-assisted heating of Zn(CH3COO)2·2H2O and NaHCO3 solution with deionized water (DI water) as the solvent. The as-synthesized ZnO powder was calcined at temperatures from 400 to 800°C for 8h. The X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) spectra revealed pure wurtzite structure for the ZnO nanopowder (NP) calcined at 800°C. Scanning electron microscopy (SEM) images showed increasing size ZnO NP with uniform size distribution with increase in calcination temperature. Significant UV emission at about 373nm has been observed in the photoluminescence (PL) spectra of the as-synthesized and calcined ZnO NP. Our results showed enhanced PL intensity with a reduced full-width at half-maximum (FWHM) for ZnO NP synthesized at higher calcination temperature. [Copyright &y& Elsevier]

Abstract: The thermal-activated carrier transfer processes in a Zn0.98Cd0.02O thin film grown by plasma-assisted molecular beam epitaxy were investigated using temperature-dependent and time-resolved photoluminescence (PL) spectroscopy. As the temperature increases from 50 to 220K, the carriers transfer from shallow to deep localized states. Additionally, the carriers escape from the deep localized states above 220K due to an activation energy of about 19meV. [Copyright &y& Elsevier]

Abstract: An original synthesis method based on X-ray irradiation produced gold nanoparticles (AuNPs) with two important properties for biomedical research: intense visible photoluminescence and very high accumulation in cancer cells. The nanoparticles, coated with MUA (11-mercaptoundecanoid acid), are very small (1.4nm diameter); the above two properties are not present for even slightly larger sizes. The small MUA-AuNPs are non-cytotoxic (except for very high concentrations) and do not interfere with cancer cell proliferation. Multimodality imaging using visible light fluorescence and X-ray microscopy is demonstrated by tracing the nanoparticle-loaded tumor cells. [Copyright &y& Elsevier]

Cd1−xZnxTe crystals were grown by the temperature gradient solution growth (TGSG). Optical properties of the Cd1−xZnxTe crystals were investigated by the photoluminescence (PL) spectroscopy. The full width at half maximum (FWHM) of 11 meV for the near band edge PL was obtained. The temperature dependent broadening of the PL line-width was fitted by the acoustic phonon, longitudinal optical phonon, and impurity interaction parameters. Defect radiative density is as low as 0.002. [Copyright &y& Elsevier]