Photons Loss Simulation during Cr:YSO Passive Q-Switched Ruby Laser Pulse Generation

The loss of photons behaviour during the passive Q-switching pulse built-up time has been simulated. This simulation preformed by numerical solution for four rate equations for Cr⁴+ : Y2 SiO5 (Cr:YSO) as a saturable absorber material with the ruby solid state laser. The ground and the first excited state of saturable absorber and the laser cavity are the essential factors of hotons bsorption, concerning of saturable absorber states contribution, they show obesity ehaviour according to molecules population for each state with the time and the first exited state lifetime . While laser cavity loss has a steady-state behaviour. The total loss behaviour decreases from maximum to minimum value through the generation time of the giant pulse (passive Q-switching pulse).