Electro-optic and magneto-optic modulations of Goos-Hanchen effect in double graphene coating waveguide with sensing applications

摘要

As the electro-optic (EO) and magneto-optic modulation (MO) effects of graphene in terahertz region, we first study the EO and MO modulations of Goos-Hanchen (GH) shift from a double graphene coating waveguide. The theoretical model of waveguide is analyzed and the corresponding calculation method is presented. The EO and MO modulations of GH shift are discussed in detail with different graphene parameters. Due to being sensitive to the electric field and magnetic field variations, the double graphene coating waveguide can be applied in field intensity detection based on GH effect. Calculation results show that maximum sensitivities of 2.99 x 10(4) mu m/V and 1.61 x 10(8) mu m/T can be realized in electric field and magnetic field sensing, respectively. Meanwhile we can adjust the applied magnetic (electric) field to achieve a higher sensitivity for a special range of electric (magnetic) field intensity to be detected. The EO and MO modulations of GH shift in the double graphene coating waveguide provide us a method to realize large GH shift at different frequency, magnetic field and electric field. Meanwhile the EO and MO modulations of beams shift can also be combined to realize more flexible and sensitive detections of electric field and magnetic field.