Generating-function approach to the moment problem for the density matrix of a single mode
Ulrike Herzog · Physical Review A · 1996
Equations are derived that express the density matrix of a single mode in terms of the normally ordered moments of the photon annihilation and creation operator and that are convergent for arbitrary radiation fields. The procedure consists of introducing a set of analytic generating functions and applying the method of analytic continuation. \textcopyright{} 1996 The American Physical Society.