[en] Drinking water treatment plants (DWTPs) need to produce water under specific quality regulations. It is well known that natural organic matter (NOM) represents the most challenging factor that affects processes optimization.

[en] Drinking Water Treatments Plants (DWTP) provide safe, high quality drinking water through different unit processes. Designed to comply with legislation requirements, they have to deal with an increasingly changing environment, water qualities, process automation, higher quality standards or new treatments, among others.

[en] Photonic integrated circuits require the ability to integrate both lasers and waveguides with low absorption and coupling loss. This technology is being developed at LLNL for digital logic gates for optical key generation circuits to facilitate secure communications. Here, we demonstrate an approach of integrating InGaAs DQW edge emitting lasers (EEL) with electron beam evaporated dielectric waveguides. The EELs are defined by electron cyclotron resonance etching (ECR). This approach results in highly anisotropic etched mirrors with smooth etched features (sidewall rms roughness = 28 (angstrom), surface rms roughness = 10 (angstrom)). The mirror is etched to form both the laser cavity and define the waveguide mesa, which accommodates a dielectric stack, where the core is aligned with the active region of the laser to achieve maximum vertical mode overlapping. The waveguides are based on SiO₂/Ta₂O₅/SiO₂ which yields a high index contrast of 0.6, resulting in low loss guides (∼2-3dB/cm). The design of the interface has taken into account the waveguide transmission loss, air gap spacing and tilt between the laser and waveguide. The critical feature for this deposition technique is its required high directionality or minimal sidewall deposition and corner effects. In the butt coupled EEL/waveguide system we have measured a slope efficiency to be as high as 0.45 W/A. We have in conclusion demonstrated a technology that allows direct coupling of a dielectric optical interconnect to a semiconductor laser monolithically fabricated on the semiconductor substrate

[en] We demonstrate a grating-router with 37nm channel spacing and 6nm FWHM in the 800-900nm range for WDM over multimode fiber. Broadband thin-film add/drop filters provide wavelength re-use enabling NxN fully non-blocking interconnection with N wavelengths

[en] Custom grown vertical zone melt (VZM) ingots of GaAs have been zone refined and zone leveled. The crystallinity, impurity concentrations, defect concentrations, and electrical properties of the ingots have been studied. Radiation detectors fabricated from the ingots have been compared to radiation detectors fabricated from commercially available vertical gradient freeze (VGF) material. Preliminary results suggest that electrical homogeneity may be a major factor in determining the performance of GaAs gamma ray detectors. Deep level EL2 concentrations were reduced in the VZM material, however gamma ray detectors fabricated from the material exhibited inferior resolution. Commercial semi-insulating bulk VGF GaAs material demonstrated much better resolution than the VZM detectors, giving best energy resolutions of 7.8% FWHM for 122 keV gamma rays and 5% FWHM for 356 keV gamma rays. (orig.)