Observation of population inversion by optical adiabatic rapid passage

Abstract

I report the observation of population inversion by optical adiabatic rapid passage. These observations, on an NH3 infrared transition with all the relevant parameters known, agree with theoretical expectations. The pressure dependence of T1, obtained by this technique, makes possible the first estimate of the collision-induced rotational lifetime of NH3 in an excited band, which is significantly longer than the rotational lifetime in the ground vibrational band. © 1974 The American Physical Society.