Semiconductor optical amplifier for next-generation data center interconnects

Optical data centers have become the technology enablers for numerous emerging bandwidth-hungry applications and services, such as artificial intelligence, 4K/8K video streaming, and social networking. This is resulting in an exponential increase in data center traffic. Similar to all the previously released Ethernet standards, the future 1.6/3.2 TbE standards are likely to adopt wavelength division multiplexed transmission in the O-band, utilizing both an increased number of wavelength channels and data rate per channel. This will increase the overall energy consumption of data center networks due to the elevated number of high-power lasers and high-sensitivity wideband transceivers within the data center. The semiconductor optical amplifier (SOA) is a promising candidate for enabling a transition toward high-capacity and energy-efficient data center networks due to their small footprint and high integrability with optical transceivers. In recent years, SOAs based on quantum dot (QD) technologies have shown great potential for WDM signal amplification using a single SOA with reduced nonlinear signal distortions and energy consumption. In this paper, we discuss various SOA technologies, with a special focus on QD-SOAs, and several applications of SOAs to develop future data center network architectures, systems, and transceiver concepts with the goal of delivering new energy-efficient physical layer technologies for optical data center interconnects.