title: Effect of absorption on the spreading of a laser beam.
abstract: The propagation characteristics of the fundamental Gaussian laser beam in absorptive and active media are investigated. There is a general reduction in the spreading of the beam on propagation in both absorptive and active media. In addition, in an active medium there is a shift of the focal plane and a reduction in the waist size of the beam.
authors.affiliation: s.r.seshadri@worldnet.att.net
authors.forename: S R
authors.initials: SR
authors.lastname: Seshadri