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This work reports the role of alpha particles generated by Americium (241Am) stripes placed inside the discharge channel in providing a bias ionized background plasma before, during, and after the discharge of the N2 TE UV laser (337.1 nm) circuit. The enhancement in stimulated radiation output characteristics in terms of gas pressure, charging voltage, and pulse width, with and without alpha particles, are shown. The increased laser yield is interpreted qualitatively through plasma impedance in the discharge circuit.

Effects of He + ion irradiation in InGaP/GaAs multilayered laser structures with 7 nm InGaAs quantum wells (QWs) have been investigated. Two versions of the ion irradiation were performed: (I) into the complete structure, and (II) into the structure after a removing the p ++ -GaAs contact layer. In case I, two-energy He + ion implantation includes a 20 keV irradiation for an isolation of p ++ -GaAs and a 170 keV irradiation for the isolation of the p-InGaP cladding layer. In case II, a one-energy (100 keV) implantation is used. Front-side photoluminescence studies show an appearance of the QW emission peak at 9260 A in ion irradiated structures. This transparency effect was attributed to a reduction in a free-carrier absorption in the InGaP layers.

We present an investigation on the spatial compositional variation in InGaP layers grown by chemical beam epitaxy (CBE) on pre-patterned substrates. Neighboring regions with 190 meV bandgap discontinuity are observed with the growth at 500°C. The development of laser structures on V-grooves that incorporate these lateral heterostructures is achieved by controlling the growth temperature during growth

The detection of trace gases is very important for a variety of applications, including the monitoring of atmospheric pollutants, industrial process control, measuring air quality in workplaces, research into fruits physiological processes and medical diagnosis of diseases through the analysis of exhaled gases. The implementation of these and many other applications requiring gas sensors able to meet high sensitivity and selectivity. In this work, a photoacoustic laser spectrometer with CO2 emission in the infrared range and a resonant photoacoustic cell was used. We obtain the resonance frequency of 2.4 kHz to photoacoustic cell, was estimated detection limit of the spectrometer for molecules of ethylene (C2H4), 16 ppbV and ammonia (NH3) 42 ppbV.