Degenerate conical emissions that appear in laser-pumped atomic sodium have been reported. The cones appear for both single- and double-pump geometries. The nonlinear medium is a small, high-density sodium-seeded flame. Earlier work that relates the cones to the process of degenerate phase conjugation is extended. The analysis for the single-pump phenomenon is formally related to amplified spontaneous emission. The double-pump case is analogous to a distributed-feedback laser. Theory and experiment are presented and discussed.
© 1990 Optical Society of America
John Pender and Lambertus Hesselink, "Degenerate conical emissions in atomic-sodium vapor," J. Opt. Soc. Am. B 7, 1361-1373 (1990)