▎ 摘　　要

In this paper, a binary to gray code converter based on graphene-plasmonic waveguides using the interference effect is proposed. The plasmonic waveguides are made of graphene nano-ribbons located on the dielectric layer. The use of graphene leads to high confinement of light, relatively low losses, and working in the mid-infrared to THz region. Based on the proposed structure, two-bit and three-bit binary to gray code converters are designed and their performance is evaluated using the finite-difference time-domain (FDTD) method. The calculated values of extinction ratio (ER) for two-bit converter are 7.22 dB and 14.83 dB for G0 and G1 bits and 8.82 dB, 5.72 dB, and 11.27 dB for G0, G1, and G2 bits in the three-bit converter. Time responses indicate the high performance of the proposed converters. Moreover, the dimensions of the two-bit and three-bit structures are 2.6 mu m(2) and 4 mu m(2), respectively, representing the high potential of these devices for use in integrated photonic systems. It is worthy to note that the converters with more bits can also be implemented using the proposed structure.