Design of Plasmonic Modulators With Vanadium Dioxide on Silicon-on-Insulator

We present design of plasmonic modulators using vanadium dioxide (VO 2 ) as modulating material realized on silicon-on-insulator (SOI) wafer with only 200 nm × 140 nm modulating section within 1 μ m × 3 μ m device footprint. By utilising the large refractive index contrast between the metallic and semiconductor phases of VO 2 , the modulator can achieve a broad working wavelength range from 1100 to 1800 nm around C-band, with a high modulation depth of 21.5 dB/ μ m. We also analyse effects of using seed layer of different dielectric materials for growing VO 2 on modulation index by exploring the mixed combination of VO 2 and different dielectric materials. Our device geometries can have potential applications in the development of next-generation miniaturised high-frequency optical modulators in silicon photonics for optical communications.