TiO2-Doped Single-Mode Fiber as Active Material for Raman Lasers

The properties of TiO2-doped fiber are considered as optoelectronic material in our work. The advantages of such fiber have been studied with the aim of its application to active medium in Raman fiber lasers. The comparison of spontaneous Raman spectra and corresponding gain profiles in TiO2-doped and GeO2-doped fiber is presented. Raman gain profiles were obtained over a broad spectral range of Stokes shifted frequencies up to 1400 cm-1(42 THz). The spectral decomposition using multimode Gaussian components has been performed for both Raman gain profiles. High accuracy analytic form of Raman gain profile of TiO2-doped fiber is obtained using 12 components. The pump power of Raman gain threshold is introduced as the function of wavelength within the telecommunication windows for both fiber types. Our spectroscopic analysis allows presenting the numerical results on lasing bandwidth and Raman gain threshold inTiO2-doped single-mode fiber. It has been shown that the lasing bandwidth in TiO2-doped fiber may be almost twice wider than the lasing bandwidth in standard GeO2-doped fiber.