Femtojoule electro-optic modulation using a silicon–organic hybrid device

Scientists have demonstrated a hybrid silicon–organic electro-optic modulator that consumes just 0.7 fJ of energy per processed data bit. Such highly energy efficient optical modulators are needed for the short-reach, high-density data interconnects of the future. The 1-mm-long device is based on a Mach–Zehnder interferometer design and is compatible with data rates of up to 40 Gbit s−1. The modulator realizes a subfemtojoule efficiency by employing silicon slot waveguides filled with a highly nonlinear organic material called DLD164, which has a very large electro-optic coefficient of 180 pm V−1. The researchers, who are from Europe, the USA and China, claim that the modulator has the lowest power consumption demonstrated to date for a non-resonant Mach–Zehnder modulator realized in any material system.