Optical nutation in a gaussian beam resonator

2014 We examine the transient behaviour of a plane-spherical resonator driven by a continuous wave and filled by an optically thin gas which is suddenly switched on exact resonance with the driving field. Contrary to previous treatments, the axial and transversal field distributions and the molecular motions through the standing wave are taken into account. This is achieved by projecting the induced gas polarization on the fundamental gaussian mode of the resonator and the results are given in a quasi analytic form. An oscillatory response is only obtained when the Rabi frequency is large with respect to the Doppler line width and for a bad quality resonator. Some of the theoretical predictions have been supported by an experiment at a 6 mm-wavelength. J. Physique 41 (1980) 837-844 AOÛT 1980, Classification Physics Abstracts 42.50 42.60D 42.65