Self-Q-Switched and Mode-Locked Cr,Nd:YAG Laser under Direct 885 nm Diode Laser Pumping

A simultaneous self-Q-switched and mode-locked laser in a direct 885 nm diode-pumped Cr,Nd:YAG crystal is demonstrated. An improvement of the slope efficiency (38.1%) in the absorbed pump power is obtained under direct pumping. Under the maximum output power of 3.36 W, the repetition rate of the Q-switched envelopes is 95 kHz and the corresponding pulse width is 400 ns. Almost 100% mode-locked modulation depth is observed at the output power of 75 mW. The repetition rate of mode-locked pulses within a Q-switched envelope is 130 MHz, and the mode-locked pulse width stays within the scale of 500 ps.