We study sub-Doppler saturation resonances at cesium molecular transitions in the absorption band B<sup>1</sup>Π<sub>u</sub> ← X<sup>1</sup>∑<sub>g</sub><sup>+</sup> near 780 nm by using a commercial diode laser. The saturation power is measured as low as 5.7 mW with the laser beam diameter of 0.1 cm. Optical saturation is associated with the optical pumping of molecular ground-state levels. The long relaxation time of ground-state levels could attract interest to electromagnetically induced transparency and quantum state memory in the molecular gas. We propose to use the molecular transitions as references for doubled-frequency sources in the communication band around 1550 nm.
© 2006 Optical Society of America
Original Manuscript: August 15, 2005
Revised Manuscript: November 8, 2005
Manuscript Accepted: November 15, 2005
Hui Chen, Hebin Li, Yuri V. Rostovtsev, Mikhail A. Gubin, Vladimir A. Sautenkov, and Marlan O. Scully, "Near-infrared saturation spectroscopy of cesium molecules using a diode laser," J. Opt. Soc. Am. B 23, 723-726 (2006)