Timing jitter reduction in diode pumped passively Q-switched laser with composite pumping pulses

Summary form only given. Compact all solid state lasers play a crucial role in the applications such as cost effective reliable laser radars and laser range finders for smart munitions where precision, light-weight, low power consumption, and ruggedness must be achieved simultaneously. For many applications it is desirable to have powerful nanosecond pulses which can be obtained by using Q-switching. Passive Q-switching with saturable absorbers has the advantage of ruggedness, simplicity, and good control of transverse mode. However, saturable absorber suffers from higher intra-cavity losses and, especially, the timing jitter. This is caused by the fluctuations within the system, such as temperature, pump power and wavelength, and the intra-cavity loss, etc. A number of jitter-reduction scheme involving combination of active-passive Q-switching have been proposed, but all of the schemes involved a large number of additional optical elements and the reduction. in jitter was not substantial. We have proposed and demonstrated a simple way to reduce timing jitter of a passively Q-switched laser with composite pumping pulse, which is composed of a long and low-power pulse and a short and high-power pulse. A reduction of more than an order of magnitude in timing jitter has been obtained for a Nd:YAG/Cr/sup 4+/:YAG laser.