Research On In-band Pumped 1.5?m Eye-Safe Self-Raman Laser

Kinds of harmful thermal effects in all-solid-state lasers limit the output performance seriously. In-band pumping could significantly diminish the quantum defect between laser photon and pump photon, thus decrease the waste heat in lasers and release the thermal effects effectively. Lasers in wavelength range of 1.5x ?m are of great use in spectral research, laser ranging, remote sensing, atmospheric sounding laser radar and so on. SRS?Stimulated Raman scattering?is one of most important nonlinear effects and one of the mature approaches to generate lasers in this region. The in-band pumping method is utilized into 1.5?m Nd:YVO₄ self-Raman laser, thermal effects are released, thus the problem that serious thermal effects limit the maximum pump power and affect the raman gain is solved, and the output power and conversion efficiency of self-Raman laser are promoted.1. Nd: YVO₄ laser in-band pumped under wave-locked 878.6nm LD, which decrease the thermal load in laser. With a maximum pump power of 37 W, 12.45 W 1342nm laser is obtained, corresponding to optical efficiency of 33.6% and slope efficiency of 34.8%2. Nd: YVO₄ self-Raman laser in-band pumped under wave-locked 878.6nm LD. With maximum pump power of 30.6W and repetition frequency of 140 k Hz, 5.2W 1525 nm stokes light is obtained, corresponding to optical efficiency of 17% and conversion efficiency with respect to absorbed pump of 19.8%.3. Nd: YVO₄ self-Raman laser in-band pumped under 914 nm LD. Output performance of Nd: YVO₄ self-Raman laser with different concentration crystals, different temperatures and different PRFs are researched. While a 1.0-at% Nd: YVO₄ crystal is used, 0.77 W 1525nm stokes light is obtained and the conversion efficiency with respect to absorbed pump power is 23%.