Researchers unite across Europe to build next-gen computing circuits.

In a pan-European initiative to push quantum computing beyond current physical and performance limits, researchers across Italy, France, and Germany are developing a new class of quantum processors using light instead of electricity, and built on glass instead of silicon.

As digital systems push the limits of classical computing, demand has grown for machines that can tackle problems beyond the reach of conventional processors. From simulating molecular interactions to optimizing logistics and power grids, certain tasks require handling variables and calculations at a scale that overwhelms even the most advanced silicon-based systems.

For more than half a century, silicon chips have been the backbone of computing, enabling an exponential rise in processing power that has revolutionized modern life. But as engineers continued to shrink the components on these chips to fit more computing power into smaller spaces, they increasingly ran into physical limitations that made it harder to keep up with today's technology.

These constraints led scientists and engineers to explore fundamentally different approaches that move beyond traditional, electron-based computation.

What followed was the emergence of an entirely new class of computing based not on improvements to existing systems, but on the physics uncovered through deeper study of nature itself.

Known as quantum computing, this process stores and handles information using particles that can exist in more than one state at the same time – following rules that only apply at the smallest scale of the physical world.

Yet almost immediately, this new system revealed its own physical limits – not of size or heat, but of control. The particles used to store and process information have proven difficult to isolate, stabilize, and manipulate with the precision needed to perform reliable operations – especially when scaled beyond the equivalent of a few bits in a conventional processor.

Although progress is made almost daily to improve quantum stability, the demands of technologies that require more processing power continue to outpace it.

As a result, researchers have begun rethinking not only the mechanics of quantum systems, but also the materials used to build them.

By exploring how light behaves in engineered structures and how glass can be used to guide that light, scientists are uncovering new pathways to make quantum computing more stable, scalable, and practical for real-world applications.

Photonic glass quantum circuit

Through a coalition of leading academic institutions and technology firms, researchers across Italy, France, and Germany are working to develop a unified quantum system built entirely from glass and driven by light.

Known as QLASS and managed by Fondazione Politecnico di Milano (the foundation affiliated with the Polytechnic University of Milan), the initiative brings together complementary capabilities across hardware, software, and systems control to construct a new class of quantum processors.

Instead of carrying electrons through silicon pathways, this architecture routes photons through transparent structures precisely engineered for quantum operations. At its core are specialized chips produced by Ephos, an Italian company focused on photonic components.

These chips are fabricated using high-purity optical substrates provided by Schott AG, a German firm known for precision glass materials.

Each chip supports up to 200 reconfigurable optical modes, allowing the system to dynamically adjust how individual particles of light move and interact across its surface.

But directing single photons through glass circuits presents its own set of technical challenges. Unlike electrical signals that travel through metal conductors, light must be confined within transparent media without being absorbed or scattered – conditions that demand exceptional structural precision and material purity.

Even minor imperfections can distort photon paths or lead to signal loss, especially at quantum scales where data is encoded in individual particles. Though the idea of transmitting light through glass may resemble fiber optic communication, the comparison stops at scale: instead of moving pulses across miles of cable, these systems must manipulate solitary photons across distances measured in microns.

This level of control begins with generation. At Sapienza University of Rome, experimental physicists are developing methods to produce single photons on demand – allowing the system to initialize computations with exact timing and state definition.

These particles are then guided into the chip, where they undergo operations according to the reconfigurable modes established in the optical hardware.

Once those operations are complete, the photons must be captured with equally high accuracy. In Germany, engineers at Pixel Photonics are designing detectors sensitive enough to register single particles of light without disturbing their quantum state.

This detection step is vital not only for validating individual results but also for maintaining coherence across longer sequences of operations.

Supporting all of this is a layer of high-speed electronics developed in Milan. These systems control the configuration of the chip's optical pathways, synchronize the emission and detection of photons, and regulate the intricate timing required to run quantum algorithms with fidelity.

Without this infrastructure, the photonic components alone would not be capable of performing stable or repeatable tasks.

On the software side, teams in France are designing the digital interfaces that translate quantum instructions into actions the hardware can execute.

Open-source platforms developed by the Unitary Foundation and the Université de Montpellier provide the operational logic that bridges theory and experiment, while researchers at the French National Centre for Scientific Research are modeling how such systems can be applied to energy-intensive problems – most notably, simulating the chemistry of lithium-ion batteries.

Taken together, these efforts support QLASS's goal of delivering a functional photonic quantum processor by 2026. Once operational, the system will be tested at Sapienza University, where its ability to model advanced materials and optimize battery performance will serve as an early benchmark for real-world utility.