Self-Mode-Locking in a Diode-Pumped Self-Q-SwitchedNd³⁺, Cr⁴⁺: YAG Laser

We report for the first time on the observation of self-mode-locking in a diode pumped self-Q-switched (SQS) Nd³⁺, Cr⁴⁺:YAG laser. This phenomenon results from significant excited state absorption of the Cr⁴⁺ ions in the co-doped host during the SQS laser pulses. The self-mode-locking occurs already slightly above the SQS laser threshold. Experiments using relatively low saturable intensity achieved a modulation depth of more than 40%.