Dynamic properties of atomic collective decay in cavity quantum electrodynamics

We theoretically study the collective decay of two atoms trapped in a single mode cavity and describe the evolution of the population of Dicke states. We show that the collective decay property is strongly dependent on the phase of atomic radiation and the speeding up of collective decay can be observed in bad cavity regime. For in- or out-phase case, it occurs due to the quantum interference enhancement no matter which atom is excited initially. For π/2 phase, the speeding up of collective decay takes place if the first atom is excited at the beginning. However, it disappears due to the quantum interference cancelation if the second atom is excited. Compared with the in-phase and out-phase cases, we also show that the speeding up of collective decay can be significantly enhanced in strong coupling regime for π/2 phase although one atom is decoupled to the cavity in this condition. The study presented here is helpful to understand the physical mechanism of collective decay in cavity quantum electrodynamics, and provide a useful method to control the collective decay phenomenon via quantum interference effect.