Effective electro-optic modulation in low-loss graphene-plasmonic slot waveguides

TL;DR

This paper demonstrates highly efficient electro-optic modulation in low-loss graphene-plasmonic slot waveguides integrated on silicon, achieving superior tunability and low insertion loss for compact optoelectronic devices.

Contribution

It introduces a novel low-loss graphene-plasmonic slot waveguide design enabling effective modulation with high tunability and minimal loss, advancing integrated optoelectronic technology.

Findings

Achieved 0.13 dB/um tunability in graphene-plasmonic waveguides.

Demonstrated low insertion loss surpassing previous devices.

Validated potential for ultra-compact active optoelectronic components.

Abstract

Surface plasmon polaritons enable light concentration within subwavelength regions, opening thereby new avenues for miniaturizing the device and strengthening light-matter interactions. Here we realize effective electro-optic modulation in low-loss plasmonic waveguides with the aid of graphene, and the devices are fully integrated in the silicon-on-insulator platform. By advantageously exploiting low-loss plasmonic slot-waveguide modes, which weakly leak into a substrate while feature strong fields within the two-layer-graphene covered slots in metal, we successfully achieve a tunability of 0.13 dB/um for our fabricated graphene-plasmonic waveguide devices with extremely low insertion loss, which outperforms previously reported graphene-plasmonic devices. Our results highlight the potential of graphene plasmonic leaky-mode hybrid waveguides to realized active ultra-compact devices for optoelectronic applications.