Cole Brian, Goldberg Lew, King Vernon, Leach Jeff
U.S. Army RDECOM CERDEC, Night Vision and Electronic Sensors Directorate, Ft. Belvoir, VA 22060 USA.
Opt Express. 2010 Apr 26;18(9):9622-7. doi: 10.1364/OE.18.009622.
UV illumination of a lithium niobate Q-switch was demonstrated as an effective means to eliminate a loss in hold-off and associated prelasing that occurs under cold temperature operation of Q-switched lasers. This degradation occurs due to the pyroelectric effect, where an accumulation of charge on crystal faces results in a reduction in the Q-switch hold-off and a spatially variable loss of the Q-switch in its high-transmission state, both resulting in lowering of the maximum Q-switched pulse energy. With UV illumination, the resulting creation of photo-generated carriers was shown to be effective in eliminating both of these effects. A Q-switched Nd:YAG laser utilizing UV-illuminated LiNbO(3) was shown to operate under cold temperatures without prelasing or spatially variable loss.
铌酸锂调Q开关的紫外线照射被证明是一种有效的方法，可以消除调Q激光器在低温工作时出现的保持时间损失和相关的预激射现象。这种退化是由于热释电效应引起的，即晶体表面电荷的积累导致调Q开关的保持时间缩短，以及调Q开关在其高透射状态下出现空间可变损耗，这两种情况都会导致最大调Q脉冲能量降低。通过紫外线照射，所产生的光生载流子被证明能有效消除这两种效应。利用紫外线照射的LiNbO(3)的调Q Nd:YAG激光器被证明在低温下工作时不会出现预激射或空间可变损耗。
