Generation of sub-Poissonian light by a four-level microlaser with a high-Q cavity

We develop a kinetic theory that describes the behavior of a monatomic four-level laser when the atom is fixed inside a high-Q optical cavity. Such a statement of the problem is similar to that used in the experiment of G. M. Meyer, H.-J. Briegel, and H. Walther [Europhys. Lett. 37, 317 (1997)]. The condition that the number of photons is large and the photon fluctuations are small is employed. We show that by selecting the parameters of the periodic electromagnetic pulses exciting the atom one can achieve regular pumping of the upper laser level and generate sub-Poissonian laser light. We also discuss the reasons why the statistical pattern of the radiation differs from the micromaser pattern with regular injection of atoms. (C) 1999 American Institute of Physics. [S1063-7761(99)00908-7].