Yang Liu

Erbium-doped fiber amplifiers (EDFA) and lasers are among the most important inventions shaping the modern internet, optical communications, and coherent sensing technologies. Their miniaturization will bring a series of significant advantages such as small size, low power consumption, flexible scalability, and high stability to next-generation information and communication technologies. However, high-performance integrated Erbium-doped light sources have remained a long-standing technical gap.

Together with the team, Yang Liu led the development of the world's first high-power photonic integrated-circuit-based erbium waveguide amplifier with output power exceeding 145 milliwatts, two orders of magnitude higher than previously reported devices. Furthermore, the amplifier approaches the performance of conventional commercial EDFAs in terms of output power, gain, and noise figure.

By fully utilizing the unique properties of erbium-doped materials and seamlessly integrating them into silicon-based photonic chips, high data rate transmission and high signal fidelity can be achieved in a compact, efficient, and scalable manner. This research makes fully integrated active silicon-based photonic chips possible, providing a breakthrough technological foundation for next-generation optical communications, photonics-assisted radar, integrated microwave photonic systems, and other application areas​.

To demonstrate the great potential of EDFA technology, Yang collaborated with Nokia Bell Labs to successfully apply the erbium-doped waveguide amplifier in the state-of-the-art coherent optical communication systems, achieving 16×1.6Tb/s coherent data transmission. Recently, with the basis of this EDWA, they achieved a fully hybrid integrated erbium laser that achieves fiber-laser coherence. The class of novel integrated light sources are being deployed in LiDAR and microwave photonic RADAR systems.

This technology has potential applications in telecommunications, data centers, and quantum computing, and compact laser sources. Currently, many internationally renowned industrial companies are eager to integrate this technology into their products​.