Members of the Helios project in Europe have demonstrated for the first time a 40-Gb/s optical modulator in silicon with a record extinction ratio of 10 dB, accomplishing a key project goal needed to build and optimize the entire supply chain for fabricating complex functional silicon-based photonic devices. Besides the 40-Gb/s modulator, Helios partners are building the fabrication supply chain through several other complex photonic integrated chips that address a variety of industrial needs, including a 16 × 10-Gb/s transceiver, a photonic QAM-10 Gb/s wireless transmission system and a mixed-analog and -digital-transceiver module for multifunction antennas. Designed and characterized at the University of Surrey in the UK, the modulator circuit was fabricated in a CMOS-compatible process by Leti, which is coordinating the project. Helios partners will present the results at the Eighth International Conference on Group IV Photonics in London, which takes place Sept. 14 to 16. ”This result is a major step towards high-bandwidth optical systems on silicon because it makes 40-Gb/s modulators viable for commercial applications,” said Graham Reed, a professor of silicon photonics at the university. Silicon photonics has generated growing interest in recent years, mainly for optical telecommunications and for optical interconnects in microelectronic circuits. CMOS photonics ultimately may be used for a range of applications, including optical communications, optical interconnections between semiconductor chips and circuit boards, optical signal processing, optical sensing and biological research. For more information, visit: www.helios-project.eu