Laser-Diode Pumped Passive Q-Switched Laser with Quick Tunable Pulse-Width Capability

A laser-diode pumped passive Q-switched Nd:YAG/Cr^4+:YAG laser with quick tunable pulse-width capability is studied and experimentally demonstrated. By focusing the auxiliary controlling laser beam onto a Cr^4+:YAG crystal and thereby changing the initial transmission of the Cr^4+:YAG crystal, laser pulses with different pulse widths can be achieved. The obtained laser pulse width is tunable in the range of 550–1492 ps with a fixed cavity length of 7 mm. The laser can be used to achieve different pulse widths between two pulses in the range of sub-nanosecond to a few tens of nanoseconds.