Analysis of Narrowband Lasing Parameters in a Random Fiber Raman Laser for Ultra-High-Resolution Spectroscopy with a Scanning Spectrometer

The parameters of narrowband lasing in a random fiber laser on stimulated Raman scattering (Raman laser) with feedback based on Rayleigh scattering, which are necessary for the implementation of ultra-high-resolution spectroscopy with a scanning single-pixel spectrum analyzer, have been analyzed. It has been shown that the correct subpixel approximation requires the mode lifetime ≥0.5 ms, intermodal interval ≥2.5 GHz, and a sufficient mode density in the unit spectral range. The laser parameters meet these requirements, which makes it possible to achieve an effective increase in the spectral resolution (to the instrument sampling step up to 1 pm).