V. M. Nesterov

CuOx CERAMIC SAMPLES PROPERTIES BEFORE AND AFTER LASER IRRADIATION

Ceramic samples of copper oxide were synthesized and their microstructure, elemental composition and electrical properties were investigated before and after the influence of YAG:Nd laser radiation. It was discovered that laser radiation leads to the fusion of granules and to a decrease in oxygen concentration in the surface layer of the sample. After the laser treatment the electrical properties of the samples pre-coated and not coated with copper film differ significantly, in particular the resistive thermal activation energy of these samples differs several times. For all the samples the current–voltage characteristics were linear at small values of the current.

Optical pumping of chemical HF lasers on the basis of NF{sub 3}-H{sub 2} and ClF{sub 5}-H{sub 2} mixtures by an open surface discharge in the bleaching-wave mode

Lasing on HF upon optical pumping by emission of an open discharge, using NF3 and ClF5 as donors of fluorine atoms, was obtained for the first time in a chemical laser and the bleaching-wave mode was realised in a chemical HF laser. An open surface discharge was used as a pump source. The velocity of the bleaching wave, which was formed under its action, reached ~8 km s-1. The formation of this wave leads to a rapid (with an ultrasonic velocity) replacement of the working medium in the lasing region, which provides a quantum laser efficiency close to unity. The optimum compo-sition of the working mixture was found to be NF3:H2:Kr =6:10:125 Torr. For this composition, the output laser energy in a 3.2-μs pulse reached ~0.4 J and the specific output energy was 3.5 J litre-1. Approximately the same output characteristics of laser emission (0.35 J in a 3.5-μs pulse in the ClF5:H2:Kr=3:20:50 Torr mixture) were obtained in the system using ClF5 as donors of fluorine atoms.

Electric-discharge XeCl laser generating 500-nsec pulses

A UV-preionized XeCI laser with active-region cross section 4 × 4 cm is investigated. We show that the use of a laser excitation system based on KMK and IK-100 capacitors makes possible a lasing pulse of 500 nsec (FWHM). The duration of the lasing pulse is found to be influenced by the components making up the working gas mixture.