NbRe Triplet Superconductor May Be Quantum Computing's Long-Sought 'Holy Grail,' Scientists Say

Scientists in Norway say a rare metal alloy called NbRe shows signs of "triplet" superconductivity, a long-sought property that could greatly stabilize quantum computers while cutting their energy use.

What Makes NbRe So Special

The new findings come from researchers at the Norwegian University of Science and Technology (NTNU), who report that NbRe, an alloy of niobium and rhenium, behaves very differently from conventional superconductors in key tests.

In a recent study published in Physical Review Letters, the team observed electrical and magnetic effects that match what physicists expect from a triplet superconductor, a material able to carry both electric current and electron spin with zero resistance.

Such materials have been described by the researchers as a technological "holy grail" for quantum computing and spintronics, according to Science Daily.

In ordinary, or "singlet," superconductors, electric current flows without resistance, but the pairs of electrons that carry the current effectively have no net spin. That makes them less useful for devices that try to use spin – a basic quantum property of electrons – to store and process information.

Triplet superconductors are different because their superconducting particles retain spin, allowing both charge and spin currents to move without energy loss. According to lead researcher Professor Jacob Linder, this could make it possible to send spin-based signals with absolutely no resistance, opening the door to ultra-fast, low-power quantum hardware.​

Why It Matters for Quantum Computing

One major promise of triplet superconductivity is that it could help keep quantum bits, or qubits, stable for longer periods. Quantum computers are extremely sensitive to tiny disturbances, which cause errors and force engineers to use complex correction schemes.

Materials that can move spin without dissipation could support new designs where information is better protected from noise. Triplet superconductors are also linked to exotic quasiparticles called Majorana modes, which many groups hope to use to build fault-tolerant qubits that resist decoherence, Academic Jobs reported.

The NTNU team worked with experimental partners in Italy to probe NbRe thin films and multilayer structures, looking for clear signatures of triplet pairing.

They report that NbRe is a non-centrosymmetric superconductor and that their measurements show an "inverse spin-valve" effect, a behavior that points to equal-spin triplet Cooper pairs inside the material. Linder said their data show NbRe acting in ways they would not expect from a standard singlet superconductor.

A practical advantage of NbRe is its relatively high critical temperature: it becomes superconducting at about 7 Kelvin, or roughly minus 266 degrees Celsius.

While still far below room temperature, this is much warmer than many earlier triplet candidates that must be cooled close to 1 Kelvin, making experiments with NbRe easier and cheaper to run.

The researchers stress that the discovery is not yet final and must be confirmed by independent groups. More tests are needed to rule out alternative explanations and fully map the triplet behavior in NbRe.

If confirmed, however, the alloy could become a key platform for future quantum devices that combine superconductivity and spintronics, bringing practical, energy-efficient quantum computing a step closer to reality, as per Interesting Engineering.