Abstract

The usual approach to the solution of a nonlinear problem in quantum optics is to solve the master equation for the density operator ρ in some discrete or continuous representation. Another method consists of deriving from the master equation an infinite hierarchy of ordinary differential equations for the moments or the correlation functions. As those are the measurable quantities we are interested in, this method is more direct. Except for some special cases where such an infinite hierarchy can be treated analytically,¹ one has to truncate the hierarchy in some way to solve the equations.

© 1990 Optical Society of America