Scientists may have found the 'holy grail' of quantum computing - Earth.com
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Quantum computers promise enormous power, but they come with a stubborn problem: they’re fragile. The tiniest disturbance – stray heat, magnetic noise, or microscopic defects – can knock delicate quantum states out of alignment and flood calculations with errors. Now, a metal alloy made from two rare transition metals – niobium and rhenium – may offer a surprising workaround. In recent experiments, the material behaved in a way that suggests it can carry not just electrical current but also preserve the tiny magnetic direction of electrons at the same time. If confirmed, this unusual behavior could help quantum engineers move both charge and spin without energy loss. That long-sought goal could ease one of quantum computing’s most persistent stability challenges. In a three-layer metal stack built around a thin film of the niobium-rhenium alloy (NbRe), electric resistance flipped in the opposite direction from what conventional superconductors allow. Analyzing that signal, Professor Jacob Linder at the Norwegian University of Science and Technology (NTNU) documented a reversal that points directly to spin-aligned electron pairing inside the alloy. Such a response runs counter to ordinary superconducting behavior, where paired electrons cancel their spins and remain indifferent to magnetic alignment. That contrast raises a sharper question about what makes triplet superconductors different, and why their spin structure could transform quantum hardware. In most superconductors, electrons move in pairs that cancel out each other’s tiny magnetic direction, so only electrical charge flows cleanly through the material. Some rare materials appear to let those pairs keep the same magnetic direction, meaning magnets do not break them apart as easily. Keeping that magnetic direction intact allows the material to carry not just electricity but also magnetic information at the same time. “Materials that are triplet superconductors are a kind of ‘holy grail’ in quantum technology, and more specifically quantum computing,” said Linder. Engineers placed the alloy between two thin magnetic layers that can point in the same or opposite directions, a setup that normally controls how easily electricity flows. When the magnets switched, the current changed in the opposite way scientists usually see in ordinary superconductors. That unexpected flip is a strong clue that the paired electrons inside the alloy were moving with the same magnetic direction instead of canceling each other out. Other possibilities still need to be ruled out, so independent teams must repeat the experiment and confirm the effect. Inside the alloy, the atoms are not arranged in a perfectly balanced mirror-image pattern. Instead, they form a slightly uneven structure – known as noncentrosymmetric – that changes how electrons pair up and move through the material. In most superconductors, electrons follow one strict pairing rule. But this uneven layout allows the alloy to blend two different pairing styles at once. That flexibility may enable the unusual current behavior seen in the experiments. Importantly, researchers believe this effect comes from the alloy’s internal structure itself – not from carefully engineered edges or special surface treatments. If that’s confirmed, it would make the material far more practical, since companies would not need to precisely fine-tune fragile boundaries to make devices function. Like all superconductors, this alloy operates at extremely low temperatures. It becomes superconducting at about 7 Kelvin (roughly -447°F). That’s still frigid, but far warmer than many superconductors that function closer to 1 Kelvin (about -458°F). Reaching 7 Kelvin is comparatively easier and could lower cooling costs, though any real quantum machine would still require powerful refrigeration. Temperature is only part of the hurdle. Quantum computers are fragile because small errors can quickly multiply across operations. Engineers combat this with quantum error correction – systems designed to detect and fix mistakes in real time. “One of the major challenges in quantum technology today is finding a way to perform computer operations with sufficient accuracy,” said Linder. Spin-carrying superconductors could help by transmitting control signals without adding heat, potentially reducing noise. Still, NbRe must integrate cleanly with qubits – the basic units of quantum information – before it can become a practical component of quantum hardware. Turning a promising material into real hardware means more than spotting an intriguing signal – it requires building repeatable layers that chip makers can pattern, connect, and test in large batches.
The team reported that NbRe can be fabricated as thin films – extremely thin deposited layers – without complicated interface engineering. Keeping the stack simple not only makes manufacturing more realistic, but also makes the physics easier to interpret, since fewer added layers can hide stray magnetic effects. Still, scaling up will demand uniform films across full wafers, and even small defects could wipe out the very behavior that makes NbRe exciting. Public attention around the NTNU result has also raised expectations, putting added pressure on the evidence. Independent teams will need to build similar magnetic stacks, reproduce the same reversed current behavior, and rule out hidden magnetic artifacts. “It is still too early to conclude once and for all whether the material is a triplet superconductor,” said Linder. Until that replication happens, NbRe remains a highly promising candidate – but not yet a ready-made ingredient for quantum devices that must operate reliably every day. Beyond quantum computing, engineers already rely on magnetism to store data. Triplet superconductors could push that control further – into the wiring itself. Designers call this approach spintronics – electronics that use the spin of electrons, rather than just their charge, to carry signals. If spin can travel through a superconductor without electrical resistance, magnetic memory could connect directly to superconducting logic with far less heating and wasted battery power. That’s where the new evidence in NbRe becomes especially important. The results tie together spin, magnetism, and superconductivity inside a single buildable structure – moving the idea from theoretical possibility toward practical hardware. Of course, real systems will still require careful engineering. Stray magnetic fields can disrupt superconductivity – a tradeoff that has limited past prototypes. Whether NbRe becomes a reliable platform for low-loss quantum control or remains an intriguing laboratory effect will depend on replication and device-level testing. The study is published in the journal Physical Review Letters. Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates. Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.