Optical induced breakdown in liquids by 0.532 /spl mu/m and 1.06 /spl mu/m short pulse lasers

In this paper, probabilistic behavior of the optical breakdown in water is investigated as a function of the laser intensity using Q-switched lasers and is compared with the breakdown probability of air in which an avalanche mechanism is believed to govern the breakdown process. The same kinds of breakdown measurement were done in solid PMMA in which avalanche ionization is not likely to occur due to the amorphous nature of PMMA. From these studies, a mechanism of optical breakdown in liquids is discussed.