Imec has demonstrated a world-first density for a superconducting circuit, packing 3.8 million Josephson junctions into one square centimeter.
The research center also produced superconducting wires just 30 nanometers wide. Imec presented both results at the 2026 Applied Superconductivity Conference (ASC).
The results could help superconducting technology scale toward future high-performance computing systems. They may also support demanding workloads running in modern US data centers.
Tiny junctions pack more
The new circuits use niobium-titanium-nitride, known as NbTiN. Imec built the circuits across three metal layers. The smallest Josephson junctions measured just 150 nanometers across. These tiny components allow engineers to fit more computing elements into less space.
A Josephson junction works like a very fast electronic switch. It can process signals while using extremely little energy.
That efficiency makes superconducting circuits interesting for high-performance computing. Imec estimates the technology could eventually offer major energy savings over conventional CMOS chips.
Superconducting systems could also support much higher computing density and bandwidth. Those advantages could become increasingly important as data centers handle heavier workloads.
The approach could prove especially useful for computing systems where moving data consumes significant power. Superconducting circuits could reduce some of those losses while handling signals at very high speeds.
Superconducting wires hit 30nm
Imec also demonstrated three layers of NbTiN wiring. The narrowest wires measured only 30nm across.
That is about 10 times narrower than wires used in conventional niobium-based superconducting technology. Smaller wires can help engineers squeeze more connections into the same amount of space.
These wires carry signals between different parts of a circuit. They can also connect components across multiple layers.
Superconductors have another major advantage. They can carry electrical current with virtually no resistance when cooled to extremely low temperatures.
That means less energy gets lost as signals travel through the system. It could help engineers tackle the growing energy demands of large computing systems.
Imec can also tune the electrical properties of its junctions and wires. This gives engineers more flexibility when designing circuits for different applications.
Superconducting chips could go further
Imec is developing the technology using 300mm semiconductor manufacturing processes. These are the same wafer dimensions widely used in modern chip production.
That compatibility could make the research easier to integrate with established semiconductor manufacturing methods. It also gives imec a path toward building larger and more complex superconducting circuits.
The research center is also working on 2.5D and 3D integration. These methods allow different components to work together within a tightly integrated system.
Richard Rouse, director of imec’s Superconducting Digital Program, said the program targets foundries, hyperscalers and system companies.
The technology could eventually move beyond high-performance computing and data centers. Imec also sees potential applications in quantum computing, photonics and neuromorphic computing.
Superconducting hardware still faces a major challenge. The circuits generally need extremely low temperatures to maintain superconductivity. That makes them harder to deploy than conventional chips.
The 3.8 million-junction density is the world’s first at this level, according to imec. The 30nm wiring demonstration also points toward smaller and more tightly packed superconducting systems.