Interference-induced enhancement of field entanglement in a microwave-driven V-type single-atom laser

We demonstrate the generation of two-mode continuous-variable (CV) entanglement in a V-type three-level atom trapped in a doubly resonant cavity using a microwave field driving a hyperfine transition between two upper excited states. By numerically simulating the dynamics of this system, our results show that the CV entanglement with large mean number of photons can be generated even in presence of the atomic relaxation and cavity losses. More interestingly, it is found that the intensity and period of entanglement can be enhanced significantly with the increasing of the atomic relaxation due to the existence of the perfect spontaneously generated interference between two atomic decay channels. Moreover, we also show that the entanglement can be controlled efficiently by tuning the intensity of spontaneously generated interference and the detuning of the cavity field.