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arXiv · 2607.07890

Measurement-Based Quantum Computing on a Photonic Chip

Jeldrik Huster·Louis L. Hohmann·Kevin Edelmann·Stefanie Barz
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Abstract

Integrated photonics provides a scalable platform for quantum information processing. In this context, measurement-based quantum computing (MBQC) offers an attractive approach in which quantum computation is realised by adaptive measurements on highly entangled graph states, circumventing the need for deterministic photon-photon interactions. Here, we demonstrate MBQC on an integrated silicon photonic chip capable of generating photonic graph states with up to four qubits. We achieve fidelities of $F_{Star} = (83.5 \pm 1.8)\,\%$ and $F_{Lin} = (75.6 \pm 1.1)\,\%$ for four-photon star and linear graph states, respectively. We use these resource states to implement MBQC-based single- and two-qubit gates and to demonstrate Grover's search algorithm and the Deutsch-Jozsa algorithm. These results establish the feasibility of reconfigurable four-photon MBQC on an integrated photonic platform and provide a foundation for future larger-scale implementations.

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Jeldrik Huster, Louis L. Hohmann, Kevin Edelmann, Stefanie Barz. 2026-07-08. Measurement-Based Quantum Computing on a Photonic Chip. https://arxiv.org/abs/2607.07890

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