Beecroft Building, Department of Physics, University of Oxford, Parks Road, Oxford, OX1 3PU
Professor Andrew White, University of Queensland
Abstract
Science and technology are intertwined, with advances in one opening up new vistas for both. In this talk, we will look at why quantum computing is interesting to scientists—as opposed to bankers and spies—and how exploring that question led us to explore whether machine learning can be accelerated by quantum phenomena.
Machine learning is widely applied in modern society, but has yet to capitalise on the unique benefits offered by quantum resources. It turns out that photons scattering through a network of beamsplitters is a powerful quantum resource: it is *very* hard to simulate, either with classical or quantum computers. Even better, it can be implemented on current quantum hardware.
We explore accelerating quantum machine learning, using quantum optics to provide a high-dimensional quantum fingerprint for reservoir computing [1,2]. We find robust performance improvements under various conditions: imperfect photon sources—even down to complete photon distinguishability; scenarios with severe class imbalances, classifying both handwritten digits and biomedical images; and sparse data, maintaining model accuracy with twenty times less training data.
Our results demonstrate that quantum photonic processors can accelerate practical ML workloads today [2]. Scaling photonic platforms, improved sampling, and applying QORC to temporal tasks represent natural directions for extending quantum reservoir computing.
[1]. A. Sakurai, A. Hayashi, W. J. Munro and K. Nemoto, Optica Quantum 3, 238 (2025)
[2]. M. Rambach, A. Roy, A. Gilchrist, A. Sakurai, W. J. Munro, K. Nemoto and A. G. White, arXiv 2512.08318 (2025)
Bio
Andrew G. White is an Australian Laureate Fellow and Professor of Physics at the University of Queensland. Raised in a Queensland dairy town, he headed south to the big smoke of Brisbane to study chemistry, maths, physics and, during the World Expo, the effects of alcohol on uni students from around the world. Deciding he wanted to know what the cold felt like, he first moved to Canberra, then Germany—completing his PhD in quantum physics—before moving on to Los Alamos National Labs in New Mexico, where he quickly discovered that there is more than enough snow to hide a cactus, but not nearly enough to prevent amusing your friends when you sit down. Over the years, he has conducted research on various topics including shrimp eyes, nuclear physics, optical vortices, and quantum computers. He likes quantum weirdness for its own sake, but his current research aims to explore and exploit the full range of quantum behaviours—notably entanglement—with an eye to engineering new technologies and scientific applications, and applying these technologies to areas such as neuromorphic computing. He is currently Director of the National Advanced Photonics Facility, and of the Quantum Technology Lab, which he established in 1999. Details can be found at https://quantum.technology.