Nonlinear noise fields and strongly driven atomic transitions

A theory of the interaction of an atom with an intense nonlinear (non-Gaussian) noise field is developed, with emphasis on the connection with the underlying physics of laser coherence. The possibility is pointed out of obtaining exact solutions for the stochastically averaged atomic density matrix in terms of (matrix) continued fractions for a large class of nonlinear noise fields by generalizing the techniques developed by Risken and co-workers to solve nonlinear Fokker-Planck equations. As an example, the absorption spectrum of an atom strongly driven by noisy phase-locked radiation is discussed.