Prompt Analysis and Design for Passively Mode-Locked Solid-State Lasers with Semiconductor Saturable Absorbers

The critical pump power for achieving passively continuous-wave mode-locking in a solid-state laser is analytically derived from the spatially dependent rate equations and the criterion for the intracavity pulse energy. A prompt way is proposed to straightforwardly design the cavity for passively mode-locked solid-state lasers. Complete experiments are performed to demonstrate the proposed cavity design and, simultaneously, to verify the theoretical model for the critical pump powers. It is interestingly observed that even though a larger modulation depth causes a higher critical pump power, it can generate a shorter pulse width in return.