Atomic coherence effects in a two-mode laser with coupled transitions.

An analytical nonperturbative theory of a two-mode laser with coupled transitions is presented. The gain medium is modeled as a homogeneously broadened A-type three-level system. Stable stationary solutions of such a two-mode laser are studied with particular attention paid to the two-photon-induced atomic- coherence effects. Our analysis shows that the nonradiative collisional decay of atomic coherence affects substantially the extent of mode competition.