Yan Yang, Qing Fang, Mingbin Yu, Xiaoguang Tu, Rusli Rusli, and Guo-Qiang Lo, "High-efficiency Si optical modulator using Cu travelling-wave electrode," Opt. Express 22, 29978-29985 (2014) http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-22-24-29978
Abstract:
We demonstrate a high-efficiency and CMOS-compatible silicon Mach-Zehnder Interferometer (MZI) optical modulator with Cu traveling wave electrode and doping compensation. The measured electro-optic
bandwidth at Vbias = −5 V is above 30 GHz when it is operated at 1550 nm. At a data rate of 50 Gbps, the dynamic extinction ratio is more than 7 dB. The phase shifter is composed of a 3 mm-long reverse-biased PN junction with modulation efficiency (Vπ·Lπ) of ~18.5 V·mm. Such a Cu-photonics technology provides an attractive potentiality for integration development of silicon photonics and CMOS circuits on SOI wafer in the future.