The optical properties of GaAs"Sbl "alloys grown across the entire concentration range by multitarget sputter deposition are reported. X-ray diffraction, optical absorption, and Raman spectra show the samples to be single-crystal, single-phase alloys for all x, including those in the miscibility gap. Alloy lattice constants are found to vary linearly with concentration. The direct I -point energy gaps, determined from optical-absorption measurements, show significant negative bowing.Contrary to previous reports, the Raman spectra exhibit two-mode behavior throughout, including a local mode of As in GaSb and a resonant mode of Sb in GaAs. An analysis of peak frequencies and line shapes versus concentration is given in the context of disorder effects. %e observe broadenings much less severe and asymmetric than those seen in similar systems and usually interpreted in terms of k&0 density-of-states activation. The observed adherence to zone-center selection rules for all x, suggests a more accurate interpretation to be one involving the k =0 spectral projection of the density of states.

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The present paper discusses an improvement for the method by division of cells which is used in multiplexed computer generated holograms (CGH´s). Such improvement allows increasing the final number of codified images into a single hologram. Some important properties of images are saved because they will be the key to perform the adequate operations involved in the reconstruction process. The experimental results demonstrate the effectiveness of the suggested procedure.

Nitrogen dioxide (NO2) was remotely measured in the urban area of San Luis Potosí (México) using the differential optical absorption spectroscopy (DOAS) technique. Measurements were taken from July to August 2015. In this technique, light scattered by the sun through the atmosphere is focused by a telescope onto a linear array-based spectrometer at ground level. During the measurement period, the maximum NO2 levels (2.3 x 1016 molecules/cm2) were found at around 11:00 h, whereas NO2 levels fell on days with wind speeds lower than 1.5 m/s. The NO2 levels were compared and explained with the behavior of meteorological data such as wind speed, relative humidity, and surface temperature obtained from the Weather Research and Forecasting Model (WRF).