We meet Felix Eltes for an interview in an unimposing office building on the outskirts of Kilchberg, near Zurich, nestled between a motorway and a gardening company. At first sight, the building’s interior gives just as little indication that it is now home to a company that wants to give the computer industry a new boost. A functional open-plan office with a multitude of computer workstations, a simple meeting room with an oversized screen for video conferencing, a small, half-filled laboratory that at first glance looks more like an arts and crafts room – this is, to put it plainly, the realm of the ETH Zurich spin-off Lumiphase, which Eltes founded in spring 2020 together with Stefan Abel, Lukas Czornomaz and Jean Fompeyrine.
But first impressions can be deceptive. The company’s 4 founders and their now 17-strong team have big plans: the components that this young company is developing will enable data to be sent back and forth between large data centres much more quickly and efficiently in the future.
Data traffic bottleneck
This is also urgently needed: because in today's digital world, there is an important interface that becoming more and more of a concern. The data that is processed and stored in electronic computer chips passes between computers along optical fibres. That means the electrical signal must be converted into an optical signal at some point and then back into an electrical signal again.
It is precisely this interface that is increasingly becoming a critical bottleneck, since the speed at which data can be exchanged also depends on how efficiently the signal is converted. Today’s technologies may be sufficient for private use, since very few home users will ever really exhaust a bandwidth of 1 Gb/s (gigabit per second) or more. But in the commercial sector, where large volumes of data have to be processed, these transmission rates are no longer sufficient. Currently, 400 Gb/s is shaping up to become the standard in this area. And with no end in sight to rapid growth in data volumes, it’s likely that even this performance will soon no longer be sufficient.
Worldwide competition
Today, electrical signals are converted into optical ones using comparatively large components that require a lot of energy. That’s why researchers around the world are feverishly searching for new ways to link the two systems as efficiently as possible.
The founders of Lumiphase are convinced that they hold very good cards in this competition. “We’ve developed a promising approach,” Eltes explains with obvious pride. At the heart of the new technology is a special material developed in recent years in a close collaboration between researchers at IBM Research in nearby Rüschlikon and ETH Zurich: barium titanate. It’s this crystal’s physical properties that make it suitable for building much smaller and more energy-efficient chips, which can also convert data more efficiently. This is because barium titanate offers an ideal combination of properties needed in the optical and electrical worlds.