Timing jitter effect in microchip laser and its reduction by backward reflection in fiber delay line

A simple, efficient, and low-cost method is proposed to reduce the timing jitter in passively Q-switched microchip lasers by self-injection seeding. A portion of the output pulse of the microchip laser was incident into the fiber delay line, and then, the backward reflection light induced the formation of the pulse. With different lengths of fiber, it was found that the timing jitter of the microchip laser could be reduced effectively when the repetition rate of the microchip laser was about 0.8 times the reciprocal of the delay time. The standard deviation of the microchip laser was reduced from several hundred nanoseconds to less than 181 ps.