A broadband hybrid plasmonic slot optical waveguide modulator based on graphene and metal nanoribbons for near-infrared applications

Amplitude modulators play a key role in modern high-speed optical communication systems, facilitating the conversation between electrical and optical signals. This study numerically demonstrates a hybrid plasmonic waveguide modulator based on graphene and metal nanoribbons, capable of achieving high-efficiency amplitude modulation and low insertion loss. Taking advantage of the adjustability of graphene conductivity and the optical waveguide’s hybrid surface plasmon polariton effects, the modulator achieves a high modulation depth of 15.12 dB/µm, an insertion loss of 1.03 dB/µm, a high-quality factor of 14.7, and a high modulation efficiency of 93.63% at the wavelength of 1550 nm. The modulator also demonstrates stable broadband modulation performance, where for a 0.4 μm long modulator, the averaged transmission coefficient S₂₁ maintains at around − 0.46 dB and around − 6.49 dB under the ON and OFF states in a wide wavelength range from 1150 to 1950 nm, respectively. This high-performance modulator may have great potential applications in high-speed optical interconnection and communication systems.