Resonance fluorescence of a two-level atom driven by a fluctuating laser field: an application of a multiple time scale method

Abstract

The authors review the various models of fluctuating laser fields which have been used in the past for the treatment of resonance fluorescence of a driven two-level atom. A new treatment of this problem in the case of a partially coherent laser field is given. This method extends that of Zoller (1977, 1978) to a large ratio of atomic decay constant to driving field frequency. The method is a kind of multiple time scale method, applied to a stochastic differential equation, and is of interest in its own right. It gives a systematic expansion in powers of the ratio of the atomic decay constant to driving field frequency, and can in principle be computed to arbitrary accuracy. Computations are presented to assess the effect of the high corrections determined.