Research On Optical Properties Of Layered Structures In Magnetoelectric Coupled Atomic Media

The essence of atomic coherence effect is the coupling between different energy levels of atomic system driven by strong laser field coherently,which can obviously change the optical properties of medium such as dispersion,refractive index and absorption,and produce some new phenomena such as electromagnetic induced transparency.This makes the atomic-gas system a popular medium for studying new optical properties in new artificial materials.In the multilevel atomic system under the double action of strong laser field and weak pumping light,the coherent coupling between the magnetic dipole transition and the electric dipole transition produces a phenomenon like electromagnetic induction transparency,such atomic system is called magnetoelectric coupled atomic medium.In this paper,the temporal cloaking phenomenon in fivelevel magnetoelectric coupled atomic medium and the polarization deflection effect in uniaxial magnetoelectric coupled atomic medium are studied.The specific work is as follows:In this paper,the research history and development status of magnetoelectric-coupled atomic medium and electromagnetic induced transparency are introduced firstly,and the significance of studying magnetoelectric-coupled atomic medium is indicated.After that,the basic concept and energy level scheme of magnetoelectric coupling atomic medium are introduced in detail,and the system scheme is modified,and the general expressions of dielectric constant,permeability,magnetoelectric coupling parameters and refractive index that related to the control field parameters of magnetoelectric coupling atomic medium are derived.Then the expressions of reflection coefficient and transmission coefficient are deduced by combining the transmission matrix of the uniaxial anisotropic magnetoelectric coupled atomic medium.In this paper,a single layer of finite thickness magnetoelectric coupled atomic medium is designed as a secure communication controller.The time-domain expression of the output optical pulses is obtained according to the group refractive index,and the temporal cloaking effect is controlled by changing the relevant parameters of the atomic medium.The results show that the Gaussian pulse generates left and right circular polarized pulses through the five-level magnetoelectric coupled atomic medium of a single layer.There are positive and negative shifts in the time domain,forming a time gap that can conceal events and prevent information leakage.The amplitude of the control field controls the positive or negative shift of the output pulse in the time domain and the size of the time gap and the phase of the control field produces the largest time gap at π/2 and π/3.The amplitudes of the two coupling fields have different effects on the size of the time gap.The thickness of the atomic medium will obviously enhance the temporal cloaking phenomenon.According to the reflection coefficient and transmission coefficient of the uniaxial anisotropic magnetoelectric coupling atomic medium derived in this paper,the expressions of the polarization conversion ratio,Faraday Angle and loss coefficient with respect to the electromagnetic parameters of the uniaxial magnetoelectric coupling atomic medium are obtained in a multilayer structure composed of vacuum and magneto-electric coupled atomic medium.The polarization deflection effect,Faraday effect and output loss of the reflected and transmitted waves are studied by simulation.The results show that full transmission is generated when the incident light enters the uniaxial magnetoelectric coupled atomic medium at a certain angle,and the polarization deflection and loss coefficient of reflection and transmission are affected by the mode of incident wave.A large degree of polarization deflection can be obtained by choosing an appropriate transverse dielectric constant component.Appropriate amplitude and detuning of control field can amplify TE electromagnetic wave.The number of structural layers will also enhance the polarization deflection of TE electromagnetic wave.