Controlling quantum coherence of V-type atom in dissipative cavity by detuning and weak measurement reversal

In this work, an interactive system composed of a V-type atom and a dissipative single-mode cavity is considered and the atomic quantum coherences are investigated under parameters including spontaneously generated interference (SGI), cavity-environment coupling, weak measurement and its reversal, and detuning between the atom and the cavity. The results indicate that strong coupling can induce coherence sudden death (CSD) and coherence sudden birth (CSB), while the non-zero SGI parameter only induces CSB. Detuning, however, may avoid both CSD and CSB. Moreover, detuning and weak measurement reversal can very effectively protect quantum coherence, while the SGI parameter, weak measurement, and strong coupling can accelerate its attenuation. The SGI parameter, detuning, weak measurement reversal, and strong coupling all promote the generation of coherence, whereas weak measurement alone can suppress it. In particular, the maximal coherent state can be very effectively protected and the coherent state can be prepared if all parameters are selected appropriately. Physical interpretations are also provided for these results.