High-speed silicon modulators for the 2 μm wavelength band

• Main Authors: Cao, Wei, Hagan, David, Thomson, David J., Nedeljkovic, Milos, Knights, Andy, Wang, Junjia, Gardes, Frederic, Zhang, Weiwei, Liu, Shenghao, Li, Ke, Xin, Guo, Wang, Wanjun, Wang, Hong, Reed, Graham T., Mashanovich, Goran Z., Littlejohns, Callum George, Shaif-Ul Alam, Mohamed Said Rouifed
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2019
• Subjects: Silicon Modulators; Wavelength Band; DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/82959; http://hdl.handle.net/10220/47618
• Institution: Nanyang Technological University

The 2 μm wavelength band has become a promising candidate to be the next communication window. We demonstrate high-speed modulators based on a 220 nm silicon-on-insulator platform working at a wavelength of 1950 nm, using the free carrier plasma dispersion effect in silicon. A Mach–Zehnder interferometer modulator and a microring modulator have been characterized. At 1950 nm, the carrier-depletion modulator operates at a data rate of 20 Gbit/s with an extinction ratio of 5.8 dB and insertion loss of 13 dB. The modulation efficiency (V ��·L ��) is 2.68 V·cm at 4 V reverse bias. The device operation is broadband, and we also characterize its performance at 1550 nm. At 1550 nm, an open eye is obtained at 30 Gbit/s. The difference in bandwidth is caused by the bandwidth limit of the 2 μm measurement setup. We also show a ring modulator paired with a low power integrated driver working in hybrid carrier depletion and injection mode at a data rate of 3 Gbit/s with power consumption of 2.38 pJ/bit in the 2 μm wavelength range. This work is a proof of principle demonstration and paves a route toward a full silicon-based transceiver in the 2 μm window.