Broadband electromagnetically induced transparency-like manipulation of graphene–black phosphorus hybrid metasurface
Yanli Xu, Hongxu Li, Yuanyuan Wu, Linfu Li, Zhengping Zhang, Shui-Jie Qin
Abstract
Abstract Plasmonics of two-dimensional materials provides a platform for enhancing light–matter interactions and offers a variety of novel applications in the terahertz range. In this work, we theoretically and numerically investigate the broadband tunable electromagnetically induced transparency-like (EIT)-like effect based on graphene–black phosphorus (G–BP) metasurface. The designed structural unit consists of a circular G–BP disk placed between two parallel G–BP strips, both of which operate in bright mode. It can achieve a broadband EIT-like effect that performs beyond individual graphene and BP films, where the underlying physical mechanism is the near-field coupling of resonator elements and the coupling of two bright-bright modes. In addition, we can flexibly adjust the transparency window of the EIT-like effect by changing the geometric parameters, polarization angle, and Fermi energy level of G–BP. The finite-difference time-domain simulation results agree well with the results of the theoretical analysis based on the coupled Lorentz oscillator model. Moreover, the proposed structure exhibits excellent dispersion accompanied with a group index of ∼60, which provides theoretical guidance for slow-light optical devices.