C-band quantum-dot lasers on monolithically grown Si platform

We are living in an increasingly digitalised world where data has become critical to all aspects of human life. Today's data centres are consuming about 3 percent of the global electricity supply and this number is likely to triple in the next decade. Remarkably, more than 50% of the power consumption in high-performance computing and data centres is associated with moving information around, rather than processing it. The current COVID-19 pandemic highlights the importance of healthcare monitoring and remote working using high speed broadband connections. Optical communications is essential to accommodate the need for high speed and bandwidth, while at the same time reducing the power required. In the meantime, 3D imaging and sensing is pushing the next revolution in consumer electronics by facilitating artificial intelligence (AI)-powered devices. LiDAR, or Light Detection and Ranging, is one of the key technologies enabling this market growth with anticipated market share reaching $6 billion by 2024, 70% of which dedicated to automotive applications.

From telecommunications to sensing applications, photons have proven to be the most efficient platform. As optical communication is penetrating to shorter and shorter distances and the 3D imaging and sensing expanding across the consumer, automotive, medical and industry/commercial sectors, the photonics manufacturing industry is on the verge of technological advancements. However, high cost, low volume capacity and limited scalability of the photon-based platform has become the bottleneck hindering cutting-edge technologies entering mass production. In this regard, integrating bulky, expensive optical components (the lasers, modulators, amplifiers, detectors and lenses) onto a much affordable and scalable platform like silicon is being much sought after by major industry and academic groups. Over the last six decades, silicon has driven the production of new technologies based on electrons at ever astounding volumes. Looking ahead, the silicon platform can be leveraged as a means to overcome the scalability, manufacturing and system architecture challenges experienced by photonics industry, impacting a range of emerging markets where small form factor, low-cost manufacturing and power efficiency are figures of merit.

In this project, we aim to integrate high-performance lasers and amplifiers operating at the strategically important C-band at 1550 nm onto the scalable silicon platform. These devices are one of the most critical components enabling long-haul optical fibre communications, inter-data centre optical interconnect and emerging 3D imaging and sensing technologies including eye-safe LiDAR chips. Leveraging the complementary growth techniques of molecular beam epitaxy (MBE) and metal organic chemical vapour deposition (MOCVD), we will incorporate manufacturable nanostructures as the gain medium to realise advanced devices surpassing state-of-the-art. Several routes will be explored to overcome the challenges in growing these materials and devices onto silicon towards fully integrated photonic platforms, opening up the opportunity for low cost and high volume mass production.