Inverted Lamb dip

Fig. 3.5 Production of inverted Lamb dip in a gas laser with an intracavity low-pressure...

Fig. 3.6 Observation of an inverted Lamb dip in a He-Ne laser at 3.39 /xm with an intracavity CH4 absorbing cell. Output power versus laser-cavity tuning, with double scan. The saturated absorption peak has an amplitude of about 2% with a 400 kHz width, and is nicely centered on the °Ne Doppler gain curve. (Reprinted from Barger and Hall 1969, with courtesy and permission of the American Physical Society.)...

E. Arimondo, P. Glorieux, T. Oka, Observation of inverted infrared lamb dips in separated optical isomers. Opt. Commun. 23 (1977) 369-372. 

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