SPECTRAL PROPERTIES OF A MICROMASER - ATOMIC-BEAM STATISTICS AND THE FIELD CORRELATION-FUNCTION

In lasers with strong atom-field coupling, Rabi-type oscillation effec ts are apparent not only in the atomic inversion and the photon number , but also in the field correlation function. Whereas the former play an important role in the standard micromaser with Poissonian injection , the latter are particularly relevant in lasers with non-Poissonian a tomic injection. In such lasers, there is generally no steady state in the usual sense, and the field correlation function is really a two-p oint correlation. We analyze the field correlation function and the sp ectrum under these circumstances. Our analysis uses a stochastic simul ation as well as an approximate analytical description. For lasers wit h a regular injection, this analysis explains the occurrence of a mult ipeak spectrum in simple terms. In the more general situation, the spe ctrum is related to the counting statistics of the atoms. Conditions f or an experimental realization are discussed.