Temporal properties of the solid-state intracavity Raman laser using the traveling-wave method

In this paper, traveling-wave (TW) equations of stimulated Raman scattering (SRS) process are deduced in detail with the phonon lifetime and backward Raman scattering considered. The numerical methods of second-order accuracy are deduced for TW equations of the SRS process. Spontaneous Raman scattering is simulated by including the stochastic shot-noise sources in phonon wave equations. The TW method is adopted to simulate the evolution of the fundamental laser inside actively Q-switched lasers, and the numerical results show periodical self-modulation of actively Q-switched pulses, which were also studied experimentally. The theoretical results were in good agreement with the experimental ones. The self-mode locking of intracavity Raman lasers are investigated numerically by adopting the TW method. It is found that the mode locking of the Stokes laser is due to the resonator net gain. The dependences of the mode-locking effect on the resonator length, transverse relaxation time of laser medium, and phonon lifetime of the Raman medium are studied numerically.