Graphene-based hybrid plasmonic optical electro-absorption modulator on InP platform

Abstract

This paper presents a novel design of an optical electro-absorption modulator based on a hybrid plasmonic structure with a graphene layer on the generic InP platform. Graphene-based optical modulators have the potential to revolutionize the field of optical communications. They enable high-speed data transfer and facilitate advancements in quantum computing. Developing a highly compact modulator on the InP platform represents a significant objective for photonics researchers aiming to achieve large-scale photonic integration technology. In the proposed design, a metal layer on top of a ridge waveguide creates a hybrid plasmonic structure. At the same time, light modulation is accomplished by applying a bias voltage to the graphene layer. By manipulating the optical absorption properties through changes in the Fermi level of the graphene layer, calculations demonstrate a 3dB bandwidth exceeding 70 GHz at λ=1.55 μm for a 1µm length. Furthermore, the impact of metal and SiO2 dielectric layer thicknesses and chemical potential on the real part of the effective index, optical absorption, 3dB bandwidth, extinction ratio, and insertion loss are quantitatively determined.