Electromagnetically Induced Grating Effect In Room-temperature Atomic System

In recent years,quantum communication has attracted the attention of researchers,and the electromagnetically induced grating with unique optical characteristics has been used to implement active control of nonlinear phase shifts,all-optical switches,quantum information processing and so on.In addition,the electromagnetically induced grating can simultaneously modulate the amplitude and phase because its significant nonlinear effects,so it is widely used in all-optical logic gates and optical communications.Therefore,scientists have been deepening the researches for the electromagnetically induced grating.The electromagnetically induced grating under the room-temperature atomic systems has attracted much attentions because of their advantages such as low costs and low technical difficulty.In this paper,we mainly studied the electromagnetically induced grating effect under the room-temperature systems.The main contents are as follows:1.The electromagnetically induced grating of N-type and tripod-type four-level in the cold atomic systems are introduced.The numerical analysis and analytical solution are used to analyze the electromagnetically induced grating.The results show that the efficiency of the first order diffraction with N-type four-level electromagnetically induced grating can be achieved 34%,and the analytical solution can be corresponded to the numerical solution.However,the analytical solution with the numerical analysis results of the tripod-type four-level electromagnetically induced grating can not be correspond well.It means that the first-order approximation of the probe light Rabi ratio is not suitable for all cases.2.A tripod-type four-level electromagnetically induced grating effect under the room-temperature atomic system was theoretically analyzed and compared with the electromagnetically induced grating effect under the cold atomic system.Numerical simulations show that the first-order diffraction efficiency under the room-temperature atomic system differs from cold atomic system by only 2.5%.Considering the high cost and equipment complexity of the cold atomic system,it is more meaningful to study the electromagnetically induced grating effect under the room temperature.The innovation of this paper:The theoretical analysis of the tripod-type four-level electromagnetically induced grating effect under the room-temperature atomic system is mainly performed.Through numerical simulation and compared with the cold atomic system,the first-order diffraction efficiency is comparable,but due to the limitations of the cold atomic system,it is very necessary to study the electromagnetically induced grating effect under the room temperature.