III-V/Si laser frequency combs for data communications

Silicon Photonics (SiPho) is a fast-growing technology addressing many applications such as data communication, sensing, imaging, and metrology to name a few. By leveraging the mature Complementary Metal Oxide Semiconductor (CMOS) processes used in electronics, high-volume and high-yield Photonic Integrated Circuits (PICs) can be fabricated at a relatively low cost. Among the major building blocks in a PIC, the multiwavelength laser source is key to scaling the capacity of the datalinks by increasing the number of communication channels. A common approach to scale the channel count by integrating multiple single-wavelength laser sources faces limitations such as increased system complexity, higher power consumption, and challenges in maintaining precise wavelength stability and uniform power distribution across channels. These issues make it difficult to achieve the desired performance and scalability in high-capacity data communication systems.

An alternative approach relies on a laser frequency comb that can deliver multiple channels from one laser cavity. Current integrated frequency comb technologies, while promising for the WDM links in datacom applications, face significant challenges. They are often limited in bandwidth, which restricts their capacity to handle large volumes of data, or suffer from efficiency and power uniformity issues, which hinder their performance and reliability in practical applications. Your research will aim to address these critical limitations by investigating new approaches to enhance bandwidth, improve efficiency, and ensure consistent power distribution across the comb spectrum. Through this work, we seek to take a leap forward in integrated frequency comb technology that can meet the growing demands of high-speed data communication systems.

Imec is currently working on the development of hybrid and monolithic III-V lasers on silicon. The aim of the development is to target highly sensitive optical receivers for the application of telecommunication, and data centers. In this context, the objective of the PhD is to research new laser cavity designs for frequency comb generation leveraging the capabilities of the 200 mm and 300 mm platforms at imec.

What you will do

The research will involve building, validating, and executing numerical models based on coupled nonlinear differential equations for the simulations of laser dynamics. The findings will drive the design of the hybrid III-V/Si laser resonators and their subsequent advanced optical characterization in state-of-the-art photonics laboratories at imec. At the end of the PhD the candidate will possess a unique knowledge and skillset in the field of nonlinear integrated photonics and III-V lasers on silicon, device physics, modeling, and characterization as well as process integration and layout design.

Expectation of workload

Literature study (10%), design modelling (20%), simulation (30%), layout (10%), characterization (30%)

What we do for you

We offer you the opportunity to join the world’s leading research center in nanotechnology at its headquarters in Leuven, Belgium. You will become part of a future team that makes the impossible possible. Together, we shape the technology that will define the society of tomorrow. We are committed to being an open multicultural and informal working environment.

Who you are

• You hold an MSc degree in the following fields: Photonics, Applied Physics, Electrical Engineering, and Optical Engineering.
• You have a theoretical or experimental background in nonlinear dynamics of semiconductor lasers and integrated nonlinear photonics or a strong interest in becoming a world expert in these areas
• Autonomy, scientific curiosity, and ability to work in an international environment.
• Hands-on exposure to photonic modelling software (e.g., Lumerical, COMSOL).
• Experience with C/C++/Python is a plus.
• Experience with GPU programming using CUDA is a plus.
• Experience with version control systems such as Git and GitHub is a plus.