TRANSVERSE PATTERN MORPHOGENESIS IN A CO2-LASER

Irregular and nonrepetitive transverse intensity distributions were me asured in the near field during the gain-switch pulse (60-ns width) of a transversely excited atmospheric CO2 laser. Transverse patterns are regular and repetitive in the long-pulse (1-mu s width) mode and in e nsemble average in the short-pulse mode, and in both cases symmetry is imposed by the boundary conditions. Short-pulse transverse patterns f ormed by lasing domains appear with a mean size of 0.8 mm. The predict ion of domain size based on a model of population inversion filamentat ion agrees with the experimental result. (C) 1996 Optical Society of A merica