Credit: Unsplash/CC0 Public Domain Researchers at Skoltech have developed an ultra-compact electro-optic modulator based on silicon photonics and plasmonics that enables high-efficiency optical signal control within a small device footprint. The development could find applications in optical communication systems, analog-to-digital conversion, as well as in devices for generating and processing ultra-high-frequency signals based on photonic technologies. The work was published in the journal Light: Advanced Manufacturing . The proposed device uses a multimode silicon waveguide of about 7 micrometers in width and 220 nanometers in thickness, with a thin layer of indium tin oxide on top. When voltage is applied, the electron concentration changes in an ultra-thin layer approximately 2 nanometers at the interface between the indium tin oxide and the insulating silicon dioxide layer. This alters the refractive index and absorption coefficient of the material, making it possible to modulate the transmitted light.…