A team from Guizhen Chip Technology, based in Hefei, in collaboration with Professor Ren Sifen's group from the Key Laboratory of Quantum Information at the University of Science and Technology of China, has presented a significant result for universal optical quantum computation.
Using a specially designed programmable photonic chip, the researchers demonstrated the generation of a GHZ state with four photons and sixteen qubits, as well as a four-qubit cluster state. Ten out of the sixteen qubits were confirmed to be genuinely entangled through entanglement witness measurements. This work represents the largest registered multi-qubit entangled state on a chip to date.
The results are highly significant because they overcome a major hurdle in photonic quantum computing technology: the exponentially poor scaling of multiphoton sources and the difficulty of creating deterministic two-photon gates. The team employs the Measurement-Based Quantum Computation (MBQC) approach, where computations are performed through single measurements on a pre-prepared entangled resource state.
To expand this resource state, the team utilizes high-dimensional encoding for each individual photon. One photon carries multiple qubits through its trajectory degree of freedom, which is then directed through a four-layer programmable measurement module. This architecture transforms the complex task of preparing multiphotons into a controlled expansion of a single high-dimensional photon plus a multilevel measurement, making the resource state preparation more deterministic while maintaining the simplicity of optical equipment.
As an additional test, the team used a four-qubit cluster state to implement Grover's search algorithm and reported an average identification probability of 0.987. This result has been published as a preprint on arXiv.
The broader significance of MBQC lies in it being the cleanest known method for achieving fault-tolerant, universal quantum computation. The model shifts the complex part of real-time logical gate operations to the prior preparation of a large entangled resource, which perfectly matches the operational mode where optical equipment can function efficiently. A derivative architecture, known as fusion-based quantum computation, inherits the properties of MBQC, possessing even higher fault-tolerance thresholds, and is a leading candidate for scaling photonic quantum hardware to the million-qubit range.
For Guizhen Chip, this work strengthens its position as the first Chinese company to demonstrate the construction of scalable graph states on a chip for photonic quantum computation. Although this result is a key building block rather than a ready-made million-qubit machine, it shifts the field of research from theoretical work to engineering milestones. The next step will be the measured demonstration of fault-tolerant logical qubits under realistic noise conditions, which is currently the focus of the global photonic quantum computing community.
Lightelligence announced the achievement of a commercialization milestone for optical computing by introducing the PACE 3 chip featuring a 256x256 photonic matrix. At the WAIC 2026 forum, the company demonstrated the world's first deployed photonic computation in real-world conditions using the Tianshu Light Cube access control system.
The PACE 3 chip is specifically designed for performing inference on large models, not for training them. It utilizes a photonic in-memory computing architecture to execute matrix-vector multiplications, which is the primary computational pattern during neural network inference. This architecture provides lower latency and better energy efficiency compared to electronic counterparts.
The hybrid photo-electric architecture addresses a fundamental problem: while photonic computing offers advantages such as high throughput, reduced transmission losses, and inherent parallel processing capability, its practical application requires integration with electronic systems for data conversion and control. The main obstacle to scaling was a contradiction: end-users saw no incentive to reconfigure software for unproven hardware, and suppliers lacked market demand to cover the costs of producing optical devices.
Lightelligence's method involves combining the capabilities of optical switching, optical interconnects, and the photonic computations themselves within its product line. This allows for the creation of integrated photo-electric solutions that do not require clients to completely overhaul their software stack. Co-founder and CTO, Dr. Meng Huaiyu, noted that the size of the photonic matrix was intentionally chosen to achieve an optimal balance, as large computations require effective coordination between matrices of different sizes, rather than one excessively large one.
Dr. Shen Yichen compared the current stage of development to creating a hardware lottery for future applications, drawing parallels with how NVIDIA's gaming processors spurred the development of neural networks. Lightelligence also places simulators in classrooms so that next-generation algorithms can evolve on photonic hardware. The company asserts that photonic computing is not a replacement for GPUs but forms an entirely new ecosystem, and the demonstration of the access control system confirms long-term operational stability.
