基于磁光材料的磁可调石墨烯多带吸收特性

Magnetically Tunable Multi-band Absorption Characteristics of Graphene Based on Magneto-optical Materials

为了改善石墨烯的吸收性能,基于石墨烯的磁光效应,提出了一种采用磁性材料构成的光子晶体异质结构。该光学结构可使石墨烯实现多带吸收。吸收带的数目可通过改变光子晶体的周期数来调节。利用4×4传输矩阵法数值研究了该光子晶体异质结构的相关参数对石墨烯吸收率的影响。结果表明:石墨烯的吸收特性表现出一定的磁圆二色性。但通过调节费米能量,在外磁场的作用,左旋圆偏振光和右旋圆偏振光均可具有较高的吸收率。研究结果为偏振光学领域石墨烯基新型光子学器件的设计制作提供了理论依据。

In order to improve the absorption performance of graphene,based on the magneto-optic effect of graphene and previous studies,a photonic crystal heterostructure composed of magnetic materials was proposed.This optical structure allowed graphene to achieve multi-band absorption.The number of absorption bands could be adjusted by changing the period number of photonic crystals.The influence of relevant parameters of the photonic crystal heterostructure on the absorption of graphene was studied by the 4×4 transfer matrix method.The results show that the absorption properties of graphene exhibit certain magnetic circular dichroism.However,by adjusting the external magnetic field and Fermi energy,the graphene can have a higher absorption for both left circularly polarized light and right circularly polarized light.The results provide a theoretical foundation for the design and fabrication of novel graphene-based photonic devices in the field of polarization optics.