Classical aspects of Raman excited rotational revivals

Abstract

The rotational coherence of Raman excited quantum wavepackets is shown to correspond to angular realignment of a classical ensemble of quantized rotors, a picture that provides an intuitive explanation for the existence and chirp shapes of four distinct partial revivals in the optical refractive index, at fractions of the full recurrence period. Evidence from the chirp shapes, of classical orientational alignment by the laser pulse (in an angle-action sense) is supported by an approximate analytically soluble quantum mechanical model.