单层石墨烯的吸收率非常低,从而一定程度上限制了其在光电子学领域的应用。基于石墨烯的磁光效应,提出利用磁光光子晶体来增强石墨烯吸收率的方案。利用4×4传输矩阵法研究了相关物理参数对石墨烯吸收率的影响。结果表明:通过调节外加磁场可以有效增强石墨烯的吸收率,石墨烯的吸收特性表现出一定的磁圆二色性;调节外加磁场的磁感应强度和费米能量,可使石墨烯对左旋圆偏振光和右旋圆偏振光均具有较高的吸收率,在一定条件下可实现近完美吸收。研究结果为基于石墨烯的高性能磁圆二色性传感器、光吸收器和光电探测器等新型光电子器件的设计及制作提供了理论依据。

A monoatomic graphene layer exhibits considerably low absorptance, limiting its application in the optoelectronics field to some extent. In this study, we propose a method of enhancing the absorption of graphene using magneto-optical photonic crystals based on the magneto-optical effect of graphene. Subsequently, the 4×4 transfer matrix method was employed to study the influence of the relevant physical parameters on the absorption of graphene. The results show that the absorption of graphene can be effectively enhanced by adjusting the external magnetic field and that the absorption properties of graphene exhibit a certain amount of magnetic circular dichroism. However, graphene can exhibit high absorption for both left and right circularly polarized light by appropriately adjusting the magnetic induction of the external magnetic field and the Fermi energy, and near-perfect absorption can be achieved under certain conditions. The results of this study provide a theoretical basis to design and fabricate novel graphene-based optoelectronic devices such as magnetic circular dichroism sensor with high-performance, optical absorbers, and photodetectors.