+44 (0)24 7671 8970
More publications     •     Advertise with us     •     Contact us
Technical Insight

Magazine Feature
This article was originally featured in the edition:
Issue 1 2024

Supporting AI with new optical modulators


To cope with surging internet traffic, datacentres can be upgraded with electro-optic polymer modulators. This technology requires no changes to the rest of the infrastructure and has performance headroom to support continual upgrades for decades.

By Michael Lebby, Chief Executive Officer, Lightwave Logic

There has long been talk of AI’s transformative potential, and the last year has made it clearer than ever that the AI revolution has begun. The technology is already reshaping many aspects of our daily lives as end users. But behind the scenes, AI is also impacting the industries and infrastructure that play a role in providing access to it. And photonics is no exception.

To understand how this trend might affect photonic integrated circuits (PICs), we must first consider how AI relates to the internet and optical networks. Although we would all like to see optical computing, and optical computational processing, this holy grail has yet to become widely commercialised like semiconductor microprocessing units (MPUs) or graphical processing units (GPUs).

Datacentres need to upgrade to meet the unabating demand for higher data rates.

For this reason, the industry currently uses photonics to send the information from MPUs and GPUs from source to destination, with fibre optic cables that form the architecture of the internet and optical network.

At the highest level, electronics does the computational processing, and is expected to continue doing so in the near future, while photonics helps convey huge amounts of generated information optically.

The photonic components that make up the communication are laser diodes, modulators, and photodetectors. These components are now becoming integrated into PICs, typically with one PIC transmitting data, and another receiving it. PICs are found in transceiver modules, which, in turn, are found in the switches and router equipment that make up a datacentre.

As surging AI usage demands higher data rates, PICs are therefore one piece of the puzzle in upgrading datacentres to meet that demand. As well as looking at the challenges posed by AI, this article describes how electro-optic polymers are driving new hybrid technologies for increased PIC performance.

High EO S21 RF bandwidth measurement of an electro-optic polymer modulator with approximate comparisons of other materials.

Skyrocketing data rates
It is widely expected that AI will substantially increase the bandwidth required to operate the internet at the speed users have come to expect. This is because AI users are increasingly experimenting with innovative ways to drive new applications which require large amounts data to be synchronously exchanged between switches and users.

In the 1980s, it would typically take tens of minutes to download a 10 Mb file, but this can be done today in less than a second. Videos were virtually impossible to download and send around back then, but today we share short video clips, even movies, with friends and family regularly. Thanks to these advances, images and videos have become the largest generators of internet traffic. But it now seems likely that AI will surpass them. Whereas it took Netflix 3.5 years to get to one million subscribers, it took ChatGPT just five days to reach the same milestone.

Additionally, over the past 60 years, computing power in high computational processing systems has skyrocketed. Its growth initially doubled every 3-5 years [1], and, since about 2020, it has increased by over an order of magnitude, to a doubling of computational power every 3-4 months in terms of petaflops [2]. Naturally, this puts strain on the infrastructure supporting it.

All parts of the network need to cope with increased quantities of information, from the fibres that optical signals travel down to the places performing optical routing and switching – which typically happens in datacentres. The financial cost for internet and optical network operators will be substantial. Further, it is not only the increased performance of sending information through the optical network that needs attention, but also ensuring power consumption is kept at reasonable levels, as data rates increase.