论文标题
通过连续共振的磁性偶极子结合状态在临界耦合处控制石墨烯的光吸收
Controlling light absorption of graphene at critical coupling through magnetic dipole quasi-bound states in the continuum resonance
论文作者
论文摘要
增强光子结构中具有高$ Q $共振的二维（2D）材料中的光 - 物质相互作用已增强光学和光子设备的开发。在本文中，我们打算在辐射工程和连续体（BIC）中建立一个桥梁，并提出了一种通过准BIC共振时控制光吸收的通用方法。在由石墨烯与硅Nanodisk metasurfaces耦合的单模两端口系统中，当磁偶极共振的辐射速率等于石墨烯的耗散损耗率时，可以达到0.5的最大吸收。此外，通过同时更改Metasurfaces的不对称参数，费米水平和石墨烯的层数，可以将吸收带宽从0.9 nm到94 nm进行两个以上的数量级。这项工作揭示了BIC在辐射工程中的重要作用，并为控制下一代光子设备的2D材料的光吸收提供了有前途的策略，例如光发射器，探测器，调节器和传感器。
Enhancing the light-matter interaction in two-dimensional (2D) materials with high-$Q$ resonances in photonic structures has boosted the development of optical and photonic devices. Herein, we intend to build a bridge between the radiation engineering and the bound states in the continuum (BIC), and present a general method to control light absorption at critical coupling through the quasi-BIC resonance. In a single-mode two-port system composed of graphene coupled with silicon nanodisk metasurfaces, the maximum absorption of 0.5 can be achieved when the radiation rate of the magnetic dipole resonance equals to the dissipate loss rate of graphene. Furthermore, the absorption bandwidth can be adjusted more than two orders of magnitude from 0.9 nm to 94 nm by simultaneously changing the asymmetric parameter of metasurfaces, the Fermi level and the layer number of graphene. This work reveals out the essential role of BIC in radiation engineering and provides promising strategies in controlling light absorption of 2D materials for the next-generation optical and photonic devices, e.g., light emitters, detectors, modulators, and sensors.
