A simple all-fiber widely tunable phosphosilicate Raman fiber laser (RFL) of high efficiency has been developed. The laser has more than 50 nm tuning range, and generates up to 3.2 W of output power with 72% maximum slope efficiency. The output power is almost constant in the range 1258-1303 nm. The width and the spectral power density of the RFL output spectrum can be controlled by the detuning of its cavity fiber Bragg gratings (FBGs) thus being optimized for efficient frequency doubling.

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This paper reports on experimental measurement of H2S absorption in the spectral range of 4860–4880 cm−1 by means of diode laser absorption spectroscopy, and determines the H2S spectral absorption line in the generation area of the laser used, most promising in terms of H2S detection using this method.

A comparative analytical review of existing methods and means of measuring hydrogen sulfide content in gasses was performed. The method of infrared laser absorption spectroscopy, which uses semiconductor diode lasers tunable in the mid-infrared range as emission sources, is proving to be one of the most promising methods for solving these problems.

P(22) absorption lines for the 13 C 16 O 2 molecule 20012-00001 vibrational band have been reported in this paper. The research has been first carried out by the diode laser absorption spectroscopy method using a single-frequency diode laser emitting in the 4860-4880 cm −1 region. The dependences of the absorption constants and cross-sections of these lines on the 13 C 16 O 2 and 12 C 16 O 2 molecules mixture concentrations in the ratio of 1:140 have been studied. The obtained results have been compared with the HITRAN spectroscopic database data.