▎ 摘 要
We propose a highly wavelength-tunable multi-mode plasmonically induced transparency (PIT) device based on monolayer graphene and graphene rings for the mid-IR region. The proposed PIT systems explore the near-field coupling and phase coupling between two graphene resonators. The multi-mode transparency windows in the spectral response have been observed in the graphene-integrated configurations. By varying the Fermi energy of the graphene, the multi-mode PIT resonance can be actively controlled without reoptimizing the geometric parameters of the structures. Based on the coupled mode theory and Fabry-Perot model, we numerically investigated the two kinds of coupling in the graphene-based PIT systems. This work may pave the ways for the further development of a compact high-performance PIT device.