Researchers at the University of Surrey have unveiled a pioneering proposal for a new type of qubit that could fundamentally shift the trajectory of quantum computing. By leveraging the unique quantum properties of superfluid helium, the team aims to overcome one of the most persistent obstacles in the field: the susceptibility of quantum systems to environmental noise as they scale in size. This breakthrough, detailed in a recent study published in npj Quantum Information, introduces the Superfluid Helium Oscillator Quantum (SHOQ) device, a design that promises significantly lower error rates than current industry-standard technologies.
Why Quantum Computers Struggle With Errors
Quantum computers represent a departure from the binary logic of classical computing, which processes information in simple bits of ones and zeros. Instead, quantum systems utilize qubits—quantum bits—that can exist in a state of superposition, allowing them to hold complex information in ways that conventional hardware cannot replicate. This computational power is the engine behind the promise of quantum technology, which aims to solve problems in drug discovery, material science, and cryptography that would take classical supercomputers centuries to calculate.
However, the path to a functional, large-scale quantum computer is fraught with technical difficulties, most notably the issue of "decoherence" or error rates. Many of today’s leading quantum platforms, including those developed by major technology firms, rely on superconducting circuits. While these circuits are efficient at performing quantum operations, they are notoriously sensitive to their environment. Even minute fluctuations in electromagnetic noise or stray electrical charges—akin to the static electricity that causes hair to cling to a balloon—can disrupt the delicate state of a qubit.
As engineers attempt to build larger processors with hundreds or even thousands of qubits, the challenge of maintaining stability becomes exponential. Each additional qubit introduces more points of failure, and controlling the noise that plagues these systems has become the central barrier to achieving practical, fault-tolerant quantum computing. This is where the University of Surrey’s Quantum Sciences Group hopes to make a definitive contribution.
A Qubit With Much Lower Predicted Error Rates
The Surrey team’s proposed solution centers on superfluid helium-3, an exotic form of liquid helium that exhibits the rare property of flowing without any friction. In their study, the researchers outline the design for the Superfluid Helium Oscillator Quantum (SHOQ) device. By utilizing charge-neutral superfluid helium as the base material, the design gains an inherent advantage: because the helium carries no electric charge, it is naturally shielded from the electromagnetic noise that causes such frequent interference in superconducting circuits.
According to the researchers, this is the first reported qubit design to be based on a superfluid. Their rigorous mathematical modeling suggests that the SHOQ device could achieve error rates approximately 100 times lower than those seen in existing superconducting qubits. This reduction in error is critical; lower error rates mean that quantum algorithms can run for longer periods without the need for constant, resource-heavy error correction, bringing the industry closer to the elusive goal of "quantum advantage."
Dr. Priya Sharma, a Daphne Jackson Fellow in Hybrid Quantum Systems at the University of Surrey’s School of Mathematics and Physics and the lead author of the study, emphasized the collaborative and calculated nature of the breakthrough. "We are not the first to think about the individual components behind this idea, but what we have done for the first time is bring them together in a microfluidic device and work out the specific details that could enable the device to function as a qubit," Dr. Sharma explained.
The team’s approach was deeply analytical, relying on established knowledge of superfluid helium physics to bridge the gap between theoretical potential and practical hardware design. "The maths tells us that it should work," she added. "We have taken what we already know about superfluid helium and quantum technologies and turned that into an educated design, with the parameters and specifications needed to build one. The next step is to make a prototype and put those predictions to the test."
Integrating New Hardware into Existing Systems
Rather than suggesting that superfluid-based technology should replace the entirety of current quantum hardware, the research team envisions a more collaborative future for quantum architecture. They argue that the SHOQ device could be seamlessly integrated with existing superconducting quantum technologies. This hybrid approach would allow engineers to play to the strengths of different materials; for example, superconducting circuits could handle high-speed logic, while the SHOQ device could handle tasks where stability and noise immunity are paramount.
The researchers identified a particularly promising role for their device as a form of quantum memory. In this configuration, the superfluid-based qubit would act as a stable, long-term storage unit for quantum information, preserving the state of the data while other, more traditional hardware carries out the complex calculations. This modular approach to quantum architecture—where different types of qubits perform specialized jobs within a single, unified system—is gaining traction as a viable pathway to scaling up quantum processors.
Dr. Eran Ginossar, an Associate Professor in the University of Surrey’s Department of Physics and the Advanced Technology Institute and a co-author of the study, believes this flexibility is key. "We don’t necessarily need one type of qubit to do everything," he noted. "Combining different quantum technologies could allow us to take advantage of the strengths of each. Superfluid helium gives us a fundamentally different type of quantum hardware to explore. If the predicted performance can be demonstrated experimentally, it could eventually work alongside existing superconducting technologies as part of a larger quantum system."
The Next Step Is Building a Prototype
With the theoretical framework established and the mathematical models showing promise, the focus of the Surrey team has now shifted to the laboratory. The immediate goal is to construct a prototype that can reproduce these predictions in a physical environment. This effort is currently being bolstered by an IAA Commercialisation Fellowship awarded to Dr. Sharma, reflecting the institutional support behind the project’s transition from paper to lab bench.
Building such a device is no small feat, as it requires operating at extremely low, near-absolute-zero temperatures to maintain the superfluid state of helium-3. However, this is not uncharted territory for the team. Researchers have successfully achieved the necessary environmental conditions in previous experiments, providing a firm foundation for the development of the SHOQ prototype.
The project is a collaborative effort led by the University of Surrey, with significant input from Professor Jens Koch of Northwestern University in the United States. Professor Koch’s involvement adds considerable weight to the research, as he was a key figure in the development of the "transmon"—the superconducting qubit design that currently serves as the backbone for many of the world’s most advanced quantum computers.
As the team prepares to move toward experimental testing, the broader quantum community will be watching closely. If the SHOQ device can deliver on its promise of significantly lower error rates, it could provide the missing link required to bridge the gap between small-scale laboratory experiments and the high-performance, fault-tolerant quantum computers that researchers believe will eventually revolutionize our digital landscape. For now, the Surrey team remains focused on the rigorous, incremental work of turning their design into reality, one experiment at a time.
