Coherent on-resonance self-focusing of optical pulses

An analysis is made of the theoretically predicted and experimentally detected on-resonance self-focusing of short optical pulses traveling in a resonant absorber. The characteristic features of this effect are demonstrated in the case of propagation of short (1 and 3 nsec) pulses of helium–neon laser radiation (λ =1.15 μ) in the plasma of a glow discharge in neon at a pressure of 0.8 Torr.