Influence of phase diffusion on atomic grating in a three-level ladder-type system in lower-level microwave-driven scheme

Abstract

In this paper, we consider a scheme for electromagnetically induced grating (EIG) in a three-level ladder type system. A strong standing microwave field of finite bandwidth is applied on lower levels of ladder type atomic system. In addition, we have also introduced two incoherent pumps in our system. A weak probe is then applied to study the diffraction intensities in the presence of phase diffusion associated with the microwave control field. It is found that phase diffusion associated with strong microwave field strongly affects diffraction intensities. We have studied the effect of different system parameters such as strength of microwave field, interaction length and detunings of both the weak probe field and microwave field. Interestingly, when all the fields are resonant and there are no pump fields, the effects of phase diffusion can be reduced by optimizing the strength of microwave control field. Our results show that the introduction of detuning in microwave control and optical probe fields result in enhancement of phase grating effects. Furthermore, our results show that the introduction of incoherent pump fields can significantly improve the diffraction intensities even in the presence of phase diffusion.