Microsoft on Tuesday unveiled its second-generation quantum chip, Majorana 2, saying its qubits now survive an average of 20 seconds — a 1,000-fold improvement over the first-generation Majorana 1 chip, whose qubits lasted only milliseconds. The company described the reliability gain as comparable to the difference between a phone that needs daily charging and one that needs charging every few years.
“We will have a quantum machine in 2029 that can solve commercially viable, reasonable problems,” said Zulfi Alam, corporate vice president of Microsoft Quantum.
The chip represents a milestone in Microsoft’s two-decade pursuit of topological quantum computing, an approach that exploits the properties of a theorized quasi-particle first predicted in the 1930s by Italian physicist Ettore Majorana. To build the chip, Microsoft had to create a novel state of matter distinct from solid, liquid, or gas. Unlike conventional approaches that use individual particles, topological qubits encode information in the braiding of quasi-particle paths, which Microsoft believes offers greater stability. The second-generation chip swaps aluminum for lead as a superconductor, a change the company’s scientists devised themselves, though the team is also using artificial intelligence to accelerate improvements.
The current Majorana 2 chip contains 12 qubits. A commercially useful quantum computer would require millions, meaning substantial further advances are needed before Microsoft’s 2029 target can be realized.
Microsoft’s topological approach has attracted considerable skepticism. The company was forced to retract a 2018 paper in the journal Nature in which it claimed to have found evidence for the Majorana particle. Henry Legg, a physicist at the University of St Andrews, told the BBC at the time of the first Majorana chip’s release in 2025 that Microsoft’s quantum research had “moved firmly away from science and entered the realm of faith.”
Jason Zander, executive vice president of Microsoft Quantum and Discovery, defended the company’s work on Tuesday, saying, “We stand behind it 100%. We really look to scientific rigor. We welcome the debate that has always been part of physics… the key thing I would tell people, go read the papers and look what’s there, go talk to the experts that we have given deep information to.”
The company is in the final stage of a quantum development program run by the U.S. Defense Advanced Research Projects Agency (Darpa), which aims to “verify and validate the firm’s utility-scale quantum computer concept.” Microsoft said it has shared all data, including commercially sensitive material, with the agency for assessment. However, the paper the company published alongside Tuesday’s announcement has not been peer-reviewed, and scientists who spoke to the BBC said they wanted more information.
Paul Stevenson, a physics professor at the University of Surrey, said the company’s timeline appeared plausible if its research findings hold up.
“Microsoft appears to have made a leap in their attempt to produce viable topological qubits,” Stevenson said. “If they succeed, they will leap from being a player with no production quantum computer, to being a serious player in the race to make the next generation of fault-tolerant machines.”
A fully realized quantum computer could take on problems that would take classical computers decades to solve, such as breaking down microplastics, developing better fertilizers, or eliminating so-called forever chemicals. Zander said he sees quantum machines as a tool to accelerate human problem-solving rather than replacing it.
“It’s not about eliminating humans, it’s about giving humans tools that can help them accelerate that process, that’s actually going to help society, I think,” he said.
The fundamental difficulty of quantum computing remains the fragility of qubits. Even tiny changes in temperature or minor vibrations can introduce errors, and extending qubit survival time is a major challenge across the industry. No company is known to have yet built a fully scalable quantum computer. Sir Demis Hassabis, co-founder of Google DeepMind, has also suggested that the limits of classical computers may not yet have been reached, adding another dimension to the debate over when and how quantum systems will prove their value.