Efficient generation of stationary light pulses due to coupling between two lower levels

A double- Λ system, the two low levels of which is connected by an additional weak intensity-modulated microwave field as the controlling fields are switched off, is exploited for efficient generation of stationary light pulse (SLP). Analytical and numerical results show that due to the constructive or destructive interference between the introduced microwave field and the atomic spin coherence, the generated SLP and the retrieved signal field can be optimized or degenerated without causing distortion through modulating the intensity and phase of the microwave field.