REGULARLY INJECTED ONE-ATOM MASER IN THE HIGH-FLUX REGIME - A NUMERICAL STUDY

We present a numerical study of the regularly injected one-atom maser in the high-flux regime, namely, when the time spacing between two con secutive injected atoms is comparable with the atom-field interaction time. Gain and losses are treated simultaneously in a general master e quation that takes into account atomic incoherent decay. At stroboscop ic times the dynamics of photon-number probability distribution is giv en by a suitably reduced Green operator, which has the form of a Marko ff matrix. We perform a spectral analysis of the Green operator, showi ng the influence of photon traps on the eigenvalues. A comparison with the opposite case of Poissonian injection and low flux is given for a wide range of the pumping parameter theta. Regular injection leads to larger gain than Poissonian, but for high values of theta the opposit e result can be found. Anomalous behaviors occur in which the normaliz ed field fluctuations are increased by regularization of pumping and d ecreased by atomic decay: these features confirm similar anomalies fou nd by other authors and are ascribed to the occurrence of nonclassical multiple-peak photon distributions and to different responses of the peaks to dissipation and gain. Atomic elastic collisions destroy any s ignature of trapping states on the stationary field. A comparison with a previously studied semiclassical model is given.