Saturation and Stark splitting of an atomic transition in a stochastic field

Abstract
The authors investigate the saturation and Stark splitting of an atomic transition in (i) a phase-diffusion field and (ii) a chaotic field of arbitrary bandwidth. The theory takes into account the infinite sequence of field-correlation functions. It is shown that a chaotic field is less effective than a phase-diffusion field in saturating a single- or multiphoton transition. This is contrary to the weak-field case, where the intensity fluctuations and the associated photon bunching make the chaotic field more effective in exciting a multiphoton transition. It is also shown that the Stark splitting of an atomic transition, as observed in double resonance, is influenced dramatically by the intensity fluctuations in the chaotic field.