Queen Mary University of London builds quantum modules like computer components

Researchers from Queen Mary University of London, Imperial College and University of Oxford have unveiled Clavina, a new modular photonic quantum computing architecture capable of combining both linear and nonlinear quantum operations within a single system. Published in Nature Photonics, this development addresses a longstanding challenge in building universal photonic quantum computers, which have previously struggled to incorporate essential nonlinear operations.

The flexible design allows for specialized quantum modules to be added or removed as required, mirroring the component-based design of conventional computers. “Photonic quantum computing has enormous potential,” said Shang Yu, first author at Imperial, “but one of its greatest limitations has been the lack of a practical way to combine scalable optical circuits with the nonlinear operations required for universal quantum computing.”

Clavina Architecture Integrates Linear and Nonlinear Photonic Operations

This achievement, detailed in Nature Photonics, addresses longstanding limitations preventing photonic quantum computers from reaching their full potential, as existing designs struggled to incorporate the necessary nonlinear capabilities for advanced algorithms. This flexibility enables a broader range of quantum computing tasks to be performed on a single platform, eliminating the need for separate, purpose-built experimental setups. The team demonstrated several advanced applications using this architecture, including large-scale quantum simulations and the generation of quantum states crucial for future error correction, calculations previously impractical with existing photonic hardware.

Experiments underpinning these demonstrations were conducted in the laboratory of Professor Ian Walmsley and Dr. Raj B. Patel at Imperial. Theoretical work led by Dr. Jinzhao Sun of Queen Mary University of London, in collaboration with Professors Vlatko Vedral from Oxford and Myungshik Kim and Roberto Bondesan from Imperial, was instrumental in the development of Clavina.

Specifically, they established the theoretical framework for quantum simulation of the Bose-Hubbard model, a key tool for understanding interacting quantum particles, and quasi-deterministic breeding of Gottesman-Kitaev-Preskill states, a new approach to universal quantum computing. This work demonstrates a flexible architecture that brings those capabilities together, creating a platform that can be adapted for many different quantum applications. The researchers emphasize that the modular design facilitates the incorporation of future technologies without requiring a complete system overhaul, allowing the platform to evolve alongside advancements in the field.

While fully fault-tolerant quantum computers remain a long-term objective, this research represents a step towards scalable quantum technologies with the potential to revolutionize materials science, chemistry, optimization, and secure communications. The international collaboration included partners from the University of Hong Kong, further solidifying the global effort to advance quantum computing capabilities.