Paul van Gerven
11 December 2020

With the release of a new generation quantum photonic processor, startup Quix wants to show the world that it has the superior technology to succeed in this emerging field.

Enschede-based Quix has announced the release of a 12×12 quantum photonic processor, the most complex of its kind the world has ever seen. The upgrade from the 8×8 version the startup started out with still won’t beat classical (super)computers by a long shot, but Quix nonetheless expects to sell a number of them. “Researchers are eager to get a taste of what this technology can do. At this stage, the interest comes from academia, but it’s growing in industry too. Every self-respecting multinational is currently exploring the possibilities of quantum computing,” says Quix CTO Jelmer Renema.

Like the widely-known ‘conventional’ quantum computer, quantum photonic processors exploit quantum mechanical phenomena to produce potentially vast computing power, but they go about it in an entirely different way. Instead of creating and manipulating delicate subatomic quantum states (qubits), photons are led through an optical chip consisting of a matrix of programmable intersections. Non-classical processing power emerges from the quantum mechanical interactions between the light particles when they meet along the way.

This light-based approach has two major advantages. A typical quantum computer is a complex and bulky experimental setup, requiring cryogenic cooling and racks of peripheral electronics. By contrast, the quantum photonic processor is ‘just’ a chip that operates at room temperature. Obviously, it also requires additional electronics, as well as a light source and a detector, but all these things easily fit on or beneath a large table. Connect the setup to a PC, and you can start programming.

20201204 Quix Jelmer Renema RRA_8813
According to Quix CTO Jelmer Renema, researchers are eager to get a taste of what his company’s technology can do.

The second advantage is cost. Quix integrates its core components on a single chip, which can be mass-produced using known manufacturing processes. Naturally, this translates to cost advantages compared to having to put together a quantum computer from distinct components.


Quix uses a particular ‘flavor’ of integrated photonics for its quantum photonic processor: the Triplex platform developed by another Enschede-based company, Lionix. Triplex is what gives Quix its competitive edge compared to similar approaches, Renema explains.

“It’s a proven and mature technology. Thanks to silicon nitride waveguides, Triplex features very low light losses compared to other integrated photonic technologies, such as plain silicon.” The lower the light losses, the farther the light can travel in the chip and hence the larger the optical matrix can be. And the larger the matrix, the more powerful the chip.

Another crucial characteristic of silicon nitride is that it allows for relatively sharp bends in the waveguides. “There are materials available with lower light losses per centimeter, but these can’t make sharp bends. This inevitably increases the dimensions of the optical components and hence lengthens the path the light needs to travel. In terms of losses per component, silicon nitride is the superior choice. It can be scaled to larger matrix sizes than what is possible using other materials. With our new product release, we want to highlight exactly that.”

Scaling up still isn’t trivial, however. Over the coming years, Quix is planning to increase the matrix size step-wise. Next up will be a 20×20 chip, which Renema thinks will garner enough interest to start selling as a plug-and-play product. To be able to beat conventional computers at certain tasks, however, at least a 50×50 matrix is required. By Renema’s estimate, that’s going to take Quix another couple of years.