▎ 摘　　要

An ultra-compact plasmonic intersection structure with wavelength-tunable functionality is proposed and investigated using the finite-difference time-domain (FDTD) method. The structure consists of four symmetrical graphene nanoribbon waveguides and a graphene nanoring resonator, which exhibits the perfect cross transmission effect. Further investigation shows that the intersection wavelength of the proposed structure can be adjusted by related parameters, such as the chemical potential of the graphene nanoribbon, the radius of the nanoring, the thickness of the substrate and the width of the graphene nanoribbon. The simulation results are validated by the phase matching theory in the nanoring. Such a device may find applications in signal intersection and demultiplexing.