▎ 摘　　要

We numerically demonstrate dynamically tuneable plasmoninduced transparency in a pi-shaped metamolecules made of graphene nanostrips by applying external static magnetic field. It is shown that for graphene nanostrips with appropriate Fermi energy, the resonant wavelength, line-shape, and the polarization of transmitted light in the mid-infrared can be effectively controlled by magnetic field. In particular, giant polarization rotation exceeding 20 degrees has been observed in asymmetric graphene metamolecules, which is further enhanced to almost 40 degrees due the Faraday effect in the applied magnetic field, at around 9 mu m wavelength, much higher frequency than the Faraday rotation observed in a semi-infinite graphene microribbons. The results offer a flexible approach for the development of compact, tunable graphene-based photonic devices. (C) 2015 Optical Society of America