An inversionless gain of anti-Stokes radiation above the oscillation threshold in an optically dense far-from-degenerate double- Α Doppler-broadened medium accompanied by Stokes gain is predicted. The outcomes are illustrated with numerical simulations applied to sodium dimer vapor. Optical switching from absorption to gain via transparency controlled by a small variation of the medium and of the driving radiation parameters, which are at a level of less than one photon per molecule, is shown.
© 2000 Optical Society of America
(020.1670) Atomic and molecular physics : Coherent optical effects
(030.1670) Coherence and statistical optics : Coherent optical effects
(190.0190) Nonlinear optics : Nonlinear optics
(190.4970) Nonlinear optics : Parametric oscillators and amplifiers
Thomas F. George and A. K. Popov, "Coherence-controlled transparency and far-from-degenerate parametric gain in a strongly absorbing Doppler-broadened medium," Opt. Lett. 25, 1364-1366 (2000)