Superfluid Helium Qubit Design Could Cut Quantum Computing Errors About 100-Fold, Researchers Calculate
A University of Surrey team proposes a device built on frictionless helium-3 that is immune to the electromagnetic noise that plagues today's qubits. No one has built it yet.
Physicists at the University of Surrey have proposed a new kind of quantum bit built from superfluid helium that their calculations say could make far fewer mistakes than today's leading qubits. The team puts the predicted error rates at around 100 times lower than conventional superconducting qubits.
The design, called the Superfluid Helium Oscillator Quantum device, or SHOQ, was published in September in the journal npj Quantum Information. It is the first reported design for a superfluid-based qubit. The work was led by Surrey's Quantum Sciences Group, including research fellow Dr. Priya Sharma and associate professor Dr. Eran Ginossar, in collaboration with Professor Jens Koch of Northwestern University, who helped develop the transmon, the widely used superconducting qubit design.
The core problem it targets is noise. Quantum computers store information in fragile states that are easily scrambled by stray electric and magnetic fields, and the errors that result are one of the main reasons large, useful quantum machines are hard to build. Superconducting qubits, the type used by many of the biggest labs, are especially sensitive to electromagnetic interference.
SHOQ attacks the problem by changing the material. It uses superfluid helium-3, an unusual liquid form of helium that flows without friction. Because the liquid is charge-neutral, it is naturally resistant to electromagnetic disturbance. The device exploits quantized oscillations in the superfluid inside a microfluidic structure, so the quantum information is carried by the motion of the fluid rather than by electrical charge.
The researchers stress that this is a theoretical result. The 100-fold figure comes from calculations, not measurements. The next step is to construct a prototype and test whether the predicted performance holds up in a real device, where fabrication flaws and unexpected noise sources often eat into promised gains.
The team does not see the device as a replacement for existing technology. Instead, they imagine it working alongside superconducting systems, and one likely role is as quantum memory, a place to store quantum information with very low error rates while superconducting qubits handle fast operations.
If the prediction survives experiment, it would address one of the central scaling obstacles in quantum computing. Correcting errors costs enormous overhead: today, many physical qubits are needed to create one reliable logical qubit. A hundred-fold drop in the underlying error rate could shrink that overhead substantially.
Plenty of designs look promising on paper and fail in the lab, and helium-3 is rare and expensive, which could complicate scaling. Still, the proposal opens a different path at a time when the field is searching for hardware that can reach the error rates needed for practical machines.
