Abstract

Using a propagation cell that discriminated against the buildup of stimulated Raman emission, we succeeded in observing self-focusing in pressurized air without interference from any competing nonlinear process. Measurements were made for air pressures between 20 and 40 atm. The data yielded a nonlinear refractive index n₂. = (2.9 ± 0.3) × 10⁻¹⁶ esu per atmosphere of air at 300 K for a 308-nm laser beam.

© 1989 Optical Society of America