Abstract

Temporal behavior of pulses from a Q-switched Nd:YAG laser with an unstable resonator can vary significantly with radial position in the beam. Our laser provides pulses with position-dependent durations spanning $8–11.5\text{\hspace{0.17em} ns}$ at $1064\text{\hspace{0.17em} nm}$ and $7–10\text{\hspace{0.17em} ns}$ at $532\text{\hspace{0.17em} nm}$. Pulses emerge first and have the longest duration at the center of the beam; they are shorter (by up to 4 ns) and increasingly delayed (by up to 10 ns) with increasing radial distance from the center. This behavior can have a dramatic effect on time-sensitive experiments, such as laser-induced incandescence of soot, if not taken into account.

© 2007 Optical Society of America

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