UT-led project tackles quantum scalability bottleneck

The University of Twente (UT) is spearheading a European project to develop a quantum computing platform based on germanium-silicon (GeSi). The properties of this CMOS-compatible material enable the creation of spin qubits for computation, while also allowing the emission of light, facilitating light-based communication between qubits.

Scalability of qubits is often limited in the ability to interact with one another, explains Floris Zwanenburg of UT’s Mesa+ Institute for Nanotechnology and coordinator of the Onchip consortium. “As the number of qubits increases, effective communication between them becomes more complex.”

GeSi, more specifically GeSi with a hexagonally ordered crystal lattice, could offer a way to overcome this bottleneck. “We’re combining spin qubits for computation and photonics for communication on a GeSi platform that’s compatible with traditional CMOS manufacturing, which could be a total game-changer for scaling quantum computers.” By combining spin qubits (electrons) with photonic communication (light), the chip bridges the gap between processing quantum information and transmitting it over long distances. According to Zwanenburg, this will significantly help solve a major bottleneck in quantum scalability.

The Onchip project is co-funded by the European Commission with 3 million euros. Next to the UT, the participants are Eindhoven University of Technology, Technische Universität München, Centre National de la Recherche Scientifique (CNRS), Universität Konstanz, Budapesti Műszaki és Gazdaságtudományi Egyetem and the Dutch company Single Quantum.