Bài báo khoa học

All-optical switching in a V-type three-level atomic medium is studied and controlled by spontaneously generated coherence (SGC), relative phase of applied fields and incoherent pumping rate. By simultaneously numerical solving the coupled Maxwell–Bloch equations for atom and field on a spatio-temporal grid, we have observed a continuous-wave probe field is switched ON or OFF by periodically modulating the coupling field intensity or the relative phase of applied fields. It also is shows that although the SGC can distort the switching probe pulse, however, under the SGC the response of the medium depends sensitively on the relative phase, and the probe field can be switched synchronous or anti-synchronous with the relative phase. On the other hand, in order to overcome the switching pulse distortion caused by SGC, we have included an incoherent pumping field. By choosing the appropriate phase and pumping rate, the fluctuations of switching probe pulse can be easily overcome. The proposed model can be useful for the design of optical switches and optical storage devices as well as possible experimental implementations.