Effect of Intracavity Loss on Output Stability and Reliability of Solid-State Mode-Locked Lasers with SESAM

Mode-locked lasers have been widely used, but high-quality stable operation is still the key factor affecting their reliability. We present a numerical simulation of the dynamics of a passively mode-locked laser using saturable absorbers, and the effects of gain and loss on output stability are discussed. The results reveal that, in the case of a sudden and intense disturbance, the laser loses its lock, and the mode-locking state can be restored by stabilizing the cavity loss, whereas the mode-locking state of the laser is more robust to the slowly changing cavity loss. The laser output energy, spectrum, and pulse width vary with the cavity loss. If slow-varying cavity losses occur during mode-locked laser operation, the laser energy, pulse width, and spectrum must be monitored in real time when there is a high requirement for energy stability, pulse width, and spectral stability.