Quantum computers are highly sensitive to electromagnetic noise, and that fragility makes errors harder to control as systems grow. Researchers at the University of Surrey have proposed a new qubit design that uses superfluid helium-3, a liquid that flows without friction, to shield quantum information from such disturbances. The device, called the Superfluid Helium Oscillator Quantum (SHOQ) device, is described in a paper in npj Quantum Information.
Because the superfluid carries no electric charge, the design could be naturally protected from stray charges and electromagnetic interference that affect today's superconducting qubits. The team's calculations predict error rates about 100 times lower than those of conventional superconducting qubits. They say this is the first reported design for a qubit based on a superfluid.
The researchers do not expect the SHOQ device to replace existing quantum hardware. Instead, it could be integrated with superconducting qubits, allowing different qubit types to handle different tasks. One longer-term possibility is using the superfluid qubit as quantum memory, storing information while other hardware performs calculations. The next step is building a prototype to test whether the predicted performance holds in practice.