Graphene Assisted TE/TM-Independent Polarizer Based on Mach–Zehnder Interferometer

We presented a versatile polarizer, independent on the polarization of the incident light, by coating the silicon waveguide with graphene. The proposed polarizer works in two operation states, namely, TE-pass state and TM-pass state, which are based on the different effective mode index variations. Therefore, it is able to combine both TE-pass and TM-pass functionalities into one single component. The proposed device provides a compact size of 70 μm × 2 μm, a high extinction ratio of 19 dB for the TE-pass state and of 21 dB for the TM-pass state. Furthermore, this device exhibits a wide working bandwidth from 1500 to 1800 nm.