Resonant spectral structures of four-wave mixing (FWM) in molecular sodium are investigated. For a double- Λ configuration with strong–weak–strong–weak fields, split components in FWM spectra induced by the strong pump fields are observed. It is shown that the split components merge into a single peak for a certain ratio of the strong field intensities. A correlation between the level-splitting effects and the saturation behavior of the FWM signal is experimentally demonstrated.
© 2001 Optical Society of America
(190.2620) Nonlinear optics : Harmonic generation and mixing
(190.4380) Nonlinear optics : Nonlinear optics, four-wave mixing
(300.6290) Spectroscopy : Spectroscopy, four-wave mixing
(300.6420) Spectroscopy : Spectroscopy, nonlinear
S. A. Babin, S. I. Kablukov, U. Hinze, E. Tiemann, and B. Wellegehausen, "Level-splitting effects in resonant four-wave mixing," Opt. Lett. 26, 81-83 (2001)