High-performance plasmonic graphene-based multiplexer/demultiplexer

This paper proposes the use of two innovative single-mode plasmonic resonator-based filters to design a two-channel multiplexer/demultiplexer that demonstrates high transmission efficiencies and small sizes below 0.042 μm2. The proposed filters utilize slits in the center of rectangular and square-shaped resonators which results in a single-mode filtering effect. The study employs numerical and theoretical analyses, specifically the finite difference time domain method and coupled-mode theory, to evaluate the designed structures. The simulation results indicate that the rectangular-based demultiplexer has a cross-talk of −34 dB, a maximum transmission efficiency of 0.93, and an amplitude modulation of 0.44 dB, while the square-shaped resonator-based demultiplexer has a maximum transmission efficiency of 0.83, an amplitude modulation of 0.1 dB, and a cross-talk of −39.5 dB. These findings suggest that the proposed structures hold potential for application in optical communication systems. [Display omitted] •The designed structures work in both multiplexing and demultiplexing modes.•The size of the structure is just 0.042 μm2, more compact than all previous designs.•The transmission factor of the multiplexer/demultiplexer is as high as 0.93.•A low cross-talk of −39.5 dB allows optimistically to realize the close waveguides in a small area.