Aegiq Ltd is a photonic quantum computing company headquartered in Sheffield, England, that is building fault-tolerant quantum computers. Its approach combines deterministic photon-source technology with silicon photonics to reduce the complexity, cost and footprint of systems, so that they can be deployed alongside existing HPC and datacentre infrastructure in compact, rack-based form. Its QGATE architecture, developed with the University of Sheffield, is built around on-demand generation of entangled photons and error correction applied directly to encoded qubits.

The company was founded in Sheffield in 2019 as a spin-out of the University of Sheffield, building on more than 20 years of quantum photonics research there. Its products include a quantum computer, quantum light sources and the LightWorks SDK. In 2025 it commissioned its first on-premises photonic quantum computer at the UK's National Quantum Computing Centre. Its Quantum Link Assurance System, developed with BT Group and OpenLightComm under Innovate UK's Small Business Research Initiative, is designed to detect covert tampering on optical fibre networks. Its tensor-network software targets simulations such as computational fluid dynamics on GPU infrastructure, and in 2026 it integrated NVIDIA Ising AI models into the calibration of its Artemis system.

Aegiq operates a fabless semiconductor model, working with foundries and manufacturing partners. It has collaborated with MBDA, IQE, PsiQuantum, Pixel Photonics and the Royal Navy, and serves customers in defence, aerospace, cybersecurity, telecoms and AI. The company opened a new headquarters in Sheffield in 2026.