Hybrid laser integration for silicon photonics platform.

摘要

Silicon photonics has attracted extensive attention in both academia and industry in recent years, as an enabling technology to address the exponentially increasing demands for communication bandwidth. It brings state-of-the-art complementary metal-oxide-semiconductor (CMOS) processing technology to the field of photonic integration. The high yield and uniformity of silicon devices make it possible to build complex photonic systems-on-chip in large production volumes. Cutting-edge device performance has been demonstrated on this platform, including high-speed modulators, photodetectors, and passive devices such as the Y-junction, waveguide crossing, and arrayed waveguide gratings. As the device library quickly matures, an integrated laser source for a transmitter remains missing from the design kit.;I demonstrated hybrid external cavity lasers by integrating reflective optical semiconductor amplifiers and silicon photonics chips. The gain chip and silicon chip can be designed and optimized independently, which is a significant advantage compared to bonding an III-V film on top of the silicon chip. Advanced optoelectronics packaging processes can be leveraged for chip alignment. Tunable C-Band (near 1550 nm) lasers with 10 mW on-chip power and less than 220 kHz bandwidth are demonstrated. O-Band lasers (operating near 1310 nm) as well as successful data transmission at 10 Gb/s and 40 Gb/s using the hybrid laser as the light source are also demonstrated. I designed a single cavity, multi wavelength laser by utilizing a quantum dot SOA, Sagnac loop and micro-ring based silicon photonics half cavity. Four lasing peaks with less than 3 dB power non-uniformity were measured, as well as 4 x 10 Gb/s error free data transmission.;In addition to my main focus on RSOA/Silicon external cavity lasers, I propose and demonstrate a novel germanium-assisted grating coupler with low loss on-and-off chip fiber coupling. A coupling efficiency of 76% at 1.55 microm and 40 nm 1 dB optical bandwidth is achieved using FDTD simulation.