Dynamics of laser-induced transients produced by nanosecond duration pulses

摘要

We have implemented an interferometric method to probe the dynamics of transients induced in absorbing water solutions with nanosecond laser pulses delivered through an optical fiber. We examined two cases corresponding to strong absorption (deposition within 30 (mu)m of the fiber tip) and moderate absorption (deposition within 500 (mu)m of the fiber tip). With strong absorption the deposited energy leads to a strong stress transient followed by development of a thermally-generated vapor bubble. Moderate absorption leads to a moderate stress transient and formation of a cavitation bubble cloud arising from tensile stresses that are produced in the absorbing fluid.