Phase Control of Electromagnetically Induced Grating in a Doppler-Broadened I⟩-Type Three-Level System

We theoretically investigate the phenomena of electromagnetically induced grating in a doppler-broadened I >-type three-level atomic system with the spontaneously generated coherence (SGC) effect enhanced by an incoherence pump. It is found that the model can effectively diffract a weak probe field into high-order direction. We attribute the enhancement of diffraction mainly to the quantum interference resulting from the cross coupling between the two decay pathways. The diffraction efficiency behaves phase and doppler broadening-dependent phenomena, and can be greatly modulated by the SGC effect. Compared to the counter-propagating case, the co-propagating setting is more suitable for the purpose considered in this paper due to the effectiveness of Doppler-free.