Research Of The Goos-H?nchen Effect And Imbert-Fedorov Effect At The Interface Of Topological Insulator And Other Materials

With the development of spintronics and semiconductor physics,it has been found that the electron spin effect as an intrinsic property is a more important property than the electron transport properties when studying semiconductors.Owing to the Spin-orbit couplint interaction,the topological insulator(TI)is a novel quantum state of matter,which is insulating in bulk and conductive in edge or surface states.This metallic surface state is protected by time reversal symmetry.Chiral metamaterials(CMMs),a kind of artificial structure which lack of mirror symmetry,have strong chirality and cause cross-polarized between the magnetic and electric fields.Due to the novel electromagnetic properties of TI and CMMs,they have great potential for existing technical limitations can be broken through.At this point,TI and CMMs have attracted the attention of scientists,the preparation,optical characteristics of TI and CMMs have become a research hotspot.In this work,we based on energy flux method which modified by Yasymoto and Oisihi et al,evaluate the Goos-H?nchen(GH)effect and Imbert-Fedorov(IF)effect at total reflection.In detail,our work includes following parts:(1)The formulas about GH shift and IF shift is presented when linear polarized beam is totally reflected at the interface between TI and CMMs.The relation between GH and IF effect and the incident angle,the strength of topological magnetoelectric polarizability(TEMP),chiral parameter is also discussed.The TEMP and chiral parameter can well regulate the strength and direction of GH effect and IF effect.When gradually enhancing the TEMP,the GH effect and IF effect of the reflection of TE wave decrease and finally the GH effect and IF effect are totally suppressed.There is a maximum value when the strength of TEMP is weak,and enhancing the chiral parameter will increase the value.The GH effect and IF effect of the reflection of TM wave are very weak when the trength of TEMP is weak,and the displacement characteristics are not influenced by the chiral parameters at the same time.When increasing the strength of TEMP,the GH effect and IF effect will be increased,the strength of TEMP is strong enough,they will be totally suppressed.The IF effect of right-circular polarized wave is generally stronger than that of the light-circular polarized wave.(2)From the Maxwell's equations and physical properties of the TI with finite surface band gap,we calculate the reflection coefficient and transmission coefficient of the beam incident on the TI with finite surface band gap.We investigate the displacements of on the interface between the normal insulator and TI with finite surface band gap.We analyze the influence of finite surface band gap on the GH and IF shifts,and discuss the difference of IF shift when the linear polarization light beam is switched from elliptical polarization light.The strength of GH effect and the IF effect of the TE reflected wave will be weaken when the decreasing of the finite surface band gap.Decreasing the finite surface band gap,the direction of the GH and IF displacement change when the reflection wave is TM wave.The elliptical polarized incident beam produces stronger IF effect than linearly polarized incident beam.