Low noise, tunable silicon photonic lasers

Silicon photonics is a truly disruptive technology that has grown tremendously in the past two decades. It has now become a recognized leader in the next generation of consumer products. These future products require realizing complex optical functionalities—chief among which is an on-chip laser. Low noise and wide tuning range are the two main important characteristics of an on-chip laser as the components required to achieve these characteristics constitute the bulk of current benchtop lasers. In this paper, we review the impact of silicon photonic chips on dramatically improving the tuning range and the noise characteristics. Two different types of technologies are reviewed— heterogeneous integration by wafer bonding and hybrid integration by butt-coupling. We cover the two most important wavelength bands for optical communications—O-band for data communication applications and C-band for telecom applications.