Optical pumping of chemical HF lasers on the basis of NF3-H-2 and ClF5-H2 mixtures by an open surface discharge in the bleaching-wave mode

Lasing on HF upon optical pumping by emission of an open discharge, using N F3 and CIF5 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 o f the bleaching wave, which was formed under its action, reached similar to 8 km s(-1). The formation of this wave leads to a rapid (with an ultrasoni c velocity) replacement of the working medium in the lasing region, which p rovides a quantum laser efficiency close to unity. The optimum composition of the working mixture was found to be NF3:H-2:Kr = 6:10:125 Torr. For this composition, the output laser energy in a 3.2-mus pulse reached similar to 0.4 J and the specific output energy was 3.5 J litre(-1). Approximately th e same output characteristics of laser emission (0.35 J in a 3.5-mus pulse in the CIF5:H-2:Kr = 3:20:50 Torr mixture) were obtained in the system usin g CIF5 as donors of fluorine atoms.