We discuss Aurora, our recent demonstration of scaling and networking in a modular architecture, as well as other recent breakthroughs on Xanadu’s path to universal, fault-tolerant photonic quantum computing. Full-text article not available; see video presentation
Abstract In the pursuit of scalable and fault-tolerant quantum computing architectures, photonic-based systems have emerged as a leading frontier. This comprehensive review examines recent advances across key industry and academic players—including iPronics, Jiuzhang (USTC), ORCA Computing, Photonic Inc., PsiQuantum, Quandela, Quix Quantum, TundraSystems, TuringQ, and Xanadu—analyzing their photonic quantum processors, current performance benchmarks, architectural designs, quantum software ecosystems, and strategies toward developing large-scale fault-tolerant photonic quantum computers. The article highlights groundbreaking experiments that leverage the unique advantages of photonic technologies and underscoring their transformative potential in the NISQ and early fault‑tolerant regimes. With the global photonics market projected to reach USD 837.8 billion by 2025, this work captures photonic quantum computing’s pivotal moment in the early fault-tolerant era, offering forward‑looking insights into how photonic quantum computers may reshape the future of quantum technologies.
In the pursuit of scalable and fault-tolerant quantum computing architectures, photonic-based quantum computers have emerged as a leading frontier. This article provides a comprehensive overview of advancements in photonic quantum computing, developed by leading industry players, examining current performance, architectural designs, and strategies for developing large-scale, fault-tolerant photonic quantum computers. It also highlights recent groundbreaking experiments that leverage the unique advantages of photonic technologies, underscoring their transformative potential. This review captures a pivotal moment of photonic quantum computing in the noisy intermediate-scale quantum (NISQ) era, offering insights into how photonic quantum computers might reshape the future of quantum computing.
Photonics offers a promising platform for quantum computing1–4, owing to the availability of chip integration for mass-manufacturable modules, fibre optics for networking and room-temperature operation of most components. However, experimental demonstrations are needed of complete integrated systems comprising all basic functionalities for universal and fault-tolerant operation5. Here we construct a (sub-performant) scale model of a quantum computer using 35 photonic chips to demonstrate its functionality and feasibility. This combines all the primitive components as discrete, scalable rack-deployed modules networked over fibre-optic interconnects, including 84 squeezers6 and 36 photon-number-resolving detectors furnishing 12 physical qubit modes at each clock cycle. We use this machine, which we name Aurora, to synthesize a cluster state7 entangled across separate chips with 86.4 billion modes, and demonstrate its capability of implementing the foliated distance-2 repetition code with real-time decoding. The key building blocks needed for universality and fault tolerance are demonstrated: heralded synthesis of single-temporal-mode non-Gaussian resource states, real-time multiplexing actuated on photon-number-resolving detection, spatiotemporal cluster-state formation with fibre buffers, and adaptive measurements implemented using chip-integrated homodyne detectors with real-time single-clock-cycle feedforward. We also present a detailed analysis of our architecture’s tolerances for optical loss, which is the dominant and most challenging hurdle to crossing the fault-tolerant threshold. This work lays out the path to cross the fault-tolerant threshold and scale photonic quantum computers to the point of addressing useful applications. A proof-of-principle study reports a complete photonic quantum computer architecture that can, once appropriate component performance is achieved, deliver a universal and fault-tolerant quantum computer.