New Zealand Researchers Report Advance in Optical Ising Machine for Hybrid Quantum Optimization
Summarize this article with:
Insider Brief New Zealand researchers have developed a hybrid optical “Coherent Ising Machine” that could provide a near-term alternative to fault-tolerant quantum computers for solving complex optimization problems. The device uses circulating optical pulses in a fibre-based system with symmetry-locking properties to achieve stable, energy-efficient computation at room temperature, enabling scalable performance and compatibility with standard telecom components. The system shows potential for applications such as drug design, traffic routing, and AI optimization, with ongoing work focused on improving stability and programmability ahead of possible near-term deployment. Image: Dr Liam Quinn, Research Fellow, Te Whai Ao — Dodd-Walls Cdentre for Quantum and Photonic Technologies. PRESS RELEASE — With the world’s first scalable, fault-tolerant quantum computer expected to be years away, a group of New Zealand researchers has developed an exciting hybrid device that could solve big, intractable problems sooner. Research Fellow, Dr Liam Quinn of Te Whai Ao — Dodd-Walls Centre is leading the work, considered of such global interest that his study has just been published in the Nature Communications journal. It marks the culmination of his PhD, collaborating with Centre colleagues: Professors Stéphane Coen and Miro Erkintalo, Associate Professor Stuart Murdoch and Research Fellow, Dr Yiqing (Ray) Xu. While IBM reckons they’ll have solved the problem by 2029 with a 200-qubit computer, Google, Amazon Web Services and Microsoft are also leading the charge with their own versions. Experts say many of these developments are experimental at best, with Microsoft arguing that a million qubits will eventually be needed for such a device to operate well. Meanwhile, in a lab on the other side of the world, New Zealand researchers and their European collaborators have made a breakthrough of their own. They’ve been working on something called a Coherent Ising Machine (CIM). The mathematical model of Ising is used to study how individual pieces of a system influence each other. The problem it solves is basically: Given many interacting yes/no choices, what combination gives the best overall outcome? This is known as optimisation. The Ising machine is sometimes referred to as a ‘toy model’, because it allows complex systems to be simplified into a form that is easier to analyse. It helps scientists understand a wide range of phenomena: from how materials become magnetic when their atomic spins align; to how diseases spread and even how opinions form within communities. Dr Quinn explains how it works. “Optical pulses of light can be made to circulate in a closed loop. With engineered interactions between these light pulses, the system naturally settles into a preferred configuration or optimal solution. In this way we let the properties of quantum physics do the work for us,” he says. In quantum physics, particles behave like waves, and in most CIMs the system has to be stabilised to capture information. But using the Kiwis’ ingenuity, the system’s symmetry can be “locked”.
The New Zealanders’ optical Ising machine is based on what’s called “spontaneous polarization symmetry breaking in a coherently driven fibre Kerr nonlinear resonator”. In their device, pulses of laser light will settle into a high or low intensity state, allowing them to be read with off-the-shelf telecom components. This platform, run over optical fibre, not only simplifies the hardware but also opens a path to more stable, high-throughput devices for applications from financial modelling to drug design. It can be used to solve extremely hard optimisation problems such as scheduling, traffic routing, protein folding and AI optimization. Ising machines already exist, but Quinn says his team’s device is exceptionally stable. “Because of its special symmetry breaking properties, we think it has an advantage. It can also operate at room temperature, continuously for over an hour. “ The machine is very energy efficient because it uses the natural, continuous dynamics of optical pulses to explore an almost infinite number of possible solutions. It’s also readily scalable. Such “probabilistic computing” is more powerful than classical computing. “We’ve gone from one pulse to 1000 pulses in a few short years. It will have its own niche, as a near-term solution. Indeed, it may be some time before powerful fault-tolerant quantum computers become widely available,” Quinn says. The next step is coding and manipulation of the machine’s chip to improve performance, strength and stability, keeping the Ising machine running over longer periods of time. Depending on progress, the machine could be operating by the end of the year. Currently funded (for the second time) by the Marsden fund, the project is also continuing under the auspices of the Dodd-Walls Centre’s Quantum Technologies Aotearoa programme. Dr Quinn says he’s eager to hear from businesses or organisations with problems they’d like to solve. He cites pre-trial simulations for drug design as one likely candidate, helping developers to begin from a more refined compound than they might have otherwise. With so many applications and increasing demand for computing power, this advance could be a real opportunity for businesses wanting to interrogate large data pools. Given that the cost to lease an hour of computing time on early quantum processing units ranges from USD$2,500 – $7,000, the Ising machine is a promising alternative.
Matt Swayne LinkedIn With a several-decades long background in journalism and communications, Matt Swayne has worked as a science communicator for an R1 university for more than 12 years, specializing in translating high tech and deep tech for the general audience. He has served as a writer, editor and analyst at The Quantum Insider since its inception. In addition to his service as a science communicator, Matt also develops courses to improve the media and communications skills of scientists and has taught courses. matt@thequantuminsider.com Share this article: