论文标题
增益辅助临界耦合，以增强石墨烯的光学吸收
Gain-assisted critical coupling for enhanced optical absorption in graphene
论文作者
论文摘要
二维（2D）材料中的光吸收增强已进入纳米光子学研究的重点。在这项工作中，我们提出了一种获得临界耦合的增益辅助方法，并证明了近红外未掺杂的单层石墨烯的最大吸收。在由装有石墨烯的光子晶体平板组成的两端口系统中，引入增益介质以调整耗散速率以匹配临界耦合的辐射速率，而临界耦合的辐射速率是可以访问的，而无需更改原始的结构几何形状。增益系数的适当调整还可以在宽波长状态内具有针对不同耦合构型的临界耦合吸收。这项工作提供了一个有力的指南，以操纵2D材料中的轻度互动，并为设计超紧凑和高性能的2D材料光学设备打开了新的途径。
Enhanced optical absorption in two-dimensional (2D) materials has recently moved into the focus of nanophotonics research. In this work, we present a gain-assisted method to achieve critical coupling and demonstrate the maximum absorption in undoped monolayer graphene in the near-infrared. In a two-port system composed of photonic crystal slab loaded with graphene, the gain medium is introduced to adjust the dissipative rate to match the radiation rate for the critical coupling, which is accessible without changing the original structural geometry. The appropriate tuning of the gain coefficient also enables the critical coupling absorption within a wide wavelength regime for different coupling configurations. This work provides a powerful guide to manipulate light-matter interaction in 2D materials and opens up a new path to design ultra-compact and high-performance 2D material optical devices.
