▎ 摘　　要

In this paper, we propose a reversible Feynman gate utilizing the interference effect for optical communications and computing. The plasmonic waveguides are created by placing a suspended graphene sheet, held by two SiO2 ridges, 10 nm above the Si ribs. The Finite-difference time-domain (FDTD) method is used to simulate the proposed gate in frequency and time domains. Simulation results show that high extinction ratios as much as (15.12 dB) and 13 dB are achievable at the wavelength of 10 mu m for the output bits P and Q, respectively. The device is immune against +/- 20% variations in the width of the Si ribs due to fabrication errors and its performance can be controlled by setting the chemical potential of the graphene sheet to a suitable value. The device has an ultra-compact footprint of 3 mu m(2), suitable for use in on-chip digital photonic applications.