Quantum Theory of the Coherently Pumped Micromaser István Németh and János Bergou University of...

Model The two-level atoms, initially prepared in a proper form of the atomic coherence*, are randomly injected into the micromaser cavity at a rate r low enough that at most one atom at a time is present inside the cavity and allowed to interact with a single mode of the maser field for a time period of τ  1/r. Here ρ aa and ρ bb are the populations and ρ ab =( ρ ba ) * are the maximally allowed coherences for a given population. Furthermore ν is the frequency of the classical field used to prepare the atomic coherence * (this frequency is not necessarily the same as the atomic transition frequency ω ab ). The parameter λ ( 0  λ  1 ) determines the degree of the injected coherence. If λ=0 no atomic coherence and if λ=1 the maximal atomic coherence is injected into the micromaser. The n-th atom is injected into the maser cavity at time t n with the initial density matrix: University of West Hungary Department of Physics *Phys. Rev. A 40, 237 (1989)