Actively Q-Switched Raman Mode with Relatively Lower Gain Coefficient for Raman Laser

Using actively Q-switched self-Raman lasers to suppress the main frequency-shifted Raman mode, so that the Raman mode with relatively lower gain coefficient is stimulated Raman scattering to output Raman light with a new wavelength. First, the theoretical derivation of the actively Q-switched normalized rate equations with two Raman modes are deduced, and the normalized Raman gain coefficient, normalized loss ratio, and normalized initial population inversion density are evaluated by the basic parameters of typical experiment and common crystals. Secondly, the influence of normalized variables on the output characteristics of two Raman light pulses are studied through numerical simulation, and the range of parameters that can realize the stimulated Raman scattering of the Raman mode with relatively lower gain coefficient is found. Finally, the normalized variable values derived from the experimental parameters are numerically simulated. The results are analyzed and the optimization scheme is given.