A critique published in Nature Wednesday calls the essential know-how behind Microsoft’s “breakthrough” quantum computing chip the Majorana 1 into query. Microsoft unveiled the chip in February 2025 and stated it featured a brand-new know-how often known as a topological qubit. Topological qubits, they stated, could be the “constructing blocks” for his or her future quantum laptop. Microsoft announced the next generation chip Majorana 2 at Construct earlier this month.
However in a peer-reviewed article, Henry Legg, a physicist on the College of St. Andrews, re-analyzed Microsoft’s information on their gadget and argued that the corporate’s researchers didn’t conclusively exhibit a working topological qubit within the first place.
Idea predicts that the electrons on this wire behave in a collective sample often known as a Majorana particle, for which the chip is known as.
Proponents of quantum computing predict that the know-how’s computational talents will advance new medication discovery, encryption, and machine studying. Corporations like Google and IBM have already demonstrated extra superior machines than Majorana 1 or 2, though presently, nobody has conclusively gotten any quantum laptop to carry out something helpful. However Microsoft claimed that Majorana 1, and subsequently Majorana 2, paved their path towards a sensible quantum laptop.
Microsoft’s design, distinctive amongst quantum computing firms, includes a tiny wire, thinner than a human hair, made from the semiconductor indium arsenide caught to a superconductor. Idea predicts that the electrons on this wire behave in a collective sample often known as a Majorana particle, for which the chip is known as. Microsoft desires to encode data within the properties of the Majorana particle. (A topological qubit is to a Majorana particle as a transistor is to silicon.)
Proponents of the Majorana particle assume it’s promising qubit materials as a result of idea predicts that when fashioned into topological qubits, the Majorana ought to compute with fewer errors than competing supplies, reminiscent of superconducting circuits pursued by IBM. This means that finally, fewer topological qubits are wanted to scale as much as a helpful quantum laptop.
That’s, if Microsoft has truly made a Majorana particle. “They haven’t convincingly proven that they’ve Majoranas,” Legg advised The Verge. “You possibly can’t make a qubit should you don’t have the Majoranas.”
In Legg’s critique, he writes that what Microsoft claims as a signature of the Majorana particle might truly be from the formation of quantum dots, that are electron-containing constructions, within the gadget. Quantum dots wouldn’t be helpful for constructing the quantum laptop. He additionally writes that Microsoft cherry-picked their information.
“You possibly can’t make a qubit should you don’t have the Majoranas.”
Microsoft’s group printed a rebuttal in Nature disputing Legg’s interpretation of their information. Legg’s critique “doesn’t represent a considerable scientific problem to our findings,” the Microsoft group wrote. Legg has not “proposed an alternate mannequin that matches all of our information,” Chetan Nayak, a physicist main Microsoft’s quantum group, advised The Verge.
Legg first posted his critique on the net physics repository arXiv on February 26, 2025, inside every week of Microsoft’s Majorana 1 announcement. It took a 12 months for Nature to conduct a peer assessment and publish his article.
In the meantime, on June 2, Microsoft introduced a brand new chip, the Majorana 2, that includes what they claimed was the subsequent era of their topological qubits. The corporate says they’ll construct a “scalable quantum laptop” by 2029. “We 100% stand behind our outcomes,” Nayak advised The Verge. “We stand by our roadmap. We stand behind our long-standing dedication to scientific rigor and dialogue.”
Legg says the corporate’s characterization of Majorana 2, which Microsoft wrote in a non-peer reviewed manuscript, suffers from comparable problems he pointed out a year ago. “Nothing on this (manuscript) resolves the basic points that so many scientists have with this firm’s earlier claims,” Legg advised The Verge.
