▎ 摘　　要

We propose an integrated device for graphene electro-optic (EO) modulation and wavelength division multiplexing (WDM) using one-dimensional photonic crystal nanobeam (1D-PCN) cavity. It can realize modulation and WDM at 1570.0 nm and 1573.2 nm simultaneously. The device consists of two EO modulators and one WDM component. Each modulator is composed of an 1D-PCN cavity side coupled to a nanowire waveguide, and monolayer graphene covers the top of the silicon slab and the 1D-PCN cavity. The resonance wavelength of the 1D-PCN cavity can be changed due to the changing of chemical potential of graphene by applying voltage. The WDM component also adopts the 1D-PCN cavity structure to realize the function of filtering. The performance of the device is calculated using three-dimensional finite-difference time-domain (3D-FDTD) method. The simulation results show that a 20 GHz modulation speed can be achieved when a voltage of 3.1 V is applied. The extinction ratio is higher than 25.8 dB, the insertion loss and the channel crosstalk are lower than 0.3 dB and - 23.3 dB, respectively.