Femtojoule modulation and frequency comb generation in silicon-organic hybrid (SOH) devices

Silicon photonics offers tremendous potential for inexpensive high-yield photonic-electronic integration by enabling fabless fabrication and joint processing of photonic and electronic circuitry. Silicon as an optical material, however, falls short of certain properties that are indispensable for high-performance devices. In particular, bulk silicon does not feature any second-order optical nonlinearity due to crystal symmetry, thereby making efficient electro-optic modulators challenging. These deficiencies can be overcome by silicon-organic hybrid (SOH) integration, which combines silicon-on-insulator (SOI) waveguides with electro-optic organic materials. We give an overview on our recent progress in the field of SOH modulators, covering highly efficient devices with energy consumptions of a few femtojoule per bit and modulator-based frequency comb generators that enable WDM data transmission at terabit/s data rates.