Focus Area

High-bandwidth and energy-efficient optical interconnects

Focus Area leaders: Weiming Yao & Reinoud Lavrijsen

Optical interconnects will need to increase in bandwidth and energy efficiency by 10x in the next 10 years

Optical interconnects replace copper ones at increasingly shorter length scales. This has led to wide-scale penetration of optical interconnects into data centers and high-performance computers, supporting exponential bandwidth growth alongside reduced power consumption. Hyperscale datacenters have a fully optical fiber-optic infrastructure, and co-packaged optics are a reality for high-end processor applications. Further scaling of interconnects onto processor chips is envisaged.​ The required bandwidth of interconnects and switches is expected to grow tenfold per decade, with a target metric of 10 Tbps interconnects per compute node and 100s of Tbps switches by 2030. The energy efficiency of transmission must go up by a similar amount.

To realize such transceivers and switches that can meet these demands, various challenges will be pursued. Novel materials, enabling large-scale integration of ultra-low power consumption components, on the order of ~fJ per bit, will be required and explored. The intimate, heterogeneous integration of photonics, electronics, and even spintronics, will be pursued, to realize few-fJ-per-bit electronic-to-photonic (and vice versa) conversion of data. And finally, end-to-end transport and switching solutions, allowing <0.25-pJ-per-bit operation, including driver electronics and digital signal processing, will be targeted, using a holistic approach.

This research brings together strong research lines in novel materials, including magneto-optic materials and light-emitting group IV semiconductors, in photonic integrated circuits, with a specialization in indium phosphide, and in electro-optical communication systems. Our world-class NanoLAB cleanroom is a key enabler here.