We present the quantum theory of the two-mode micromaser operating on Λ-type three-level atoms. The explicit expression of the detailed-balance steady-state photon distribution is derived. The photon statistics and the correlation between the modes are studied. It is shown that due to the strong anticorrelation between the modes the fluctuations in the total number of photons may be sub-Poissonian even when the fluctuations in the number of photons in each mode are super-Poissonian.

• Received 23 August 1993

DOI:https://doi.org/10.1103/PhysRevA.49.1367