Microsoft’s Majorana 2 chip is 1,000× more reliable

Microsoft introduced Majorana 2 at its Build conference on Tuesday, saying the topological quantum chip is about 1,000 times more reliable than the prior generation. The company reported average qubit lifetimes near 20 seconds, with some qubits lasting up to one minute.

Microsoft described a design change that replaces an aluminum-based topological superconductor with a lead-based version to reduce interference. The company also highlighted a more compact qubit layout and said the combined changes improved both reliability and operational speed. Microsoft Technical Fellow Chetan Nayak described the progress as “1,000 times better” compared with the previous year and repeated the company’s goal of delivering a scalable quantum computer by 2029.

Microsoft attributed the advances in part to its Microsoft Discovery platform and agentic AI tools. In a company blog, engineers said the tools helped analyze decades of research, identify candidate materials, automate complex measurement routines, optimize fabrication steps and find manufacturing flaws. Zulfi Alam, corporate vice president for quantum, described the AI as able to run many voltage adjustments in parallel and find optimal operating points faster than manual experiments.

The announcement renewed discussion about the risk that sufficiently powerful quantum computers could break widely used public-key cryptography. Security analysts define “Q-Day” as the point when a quantum computer can derive private keys from public keys and forge digital signatures. Analysts have warned that Bitcoin may be especially exposed because many addresses have publicly revealed keys; one estimate cited about $461 billion worth of Bitcoin potentially at risk if current cryptographic protections are broken.

A recent research note from Citi argued that Bitcoin could be more vulnerable than other blockchains, citing differences in technical practices and governance. A technical report from Project Eleven projected a cryptographically relevant quantum computer could appear within four to seven years, a timeline that would require rapid adoption of quantum-resistant signatures to protect digital assets.

Other organizations have reported progress on reducing quantum error rates and on resource estimates for cryptographic attacks. Researchers have stated that some recent chips and academic work point to lower error rates and fewer required quantum resources than earlier estimates. Public estimates for when a machine could threaten current cryptography vary, with some projections near 2030 and others later in the decade.

Microsoft framed Majorana 2 as an incremental step on a multi-year development path and did not present a complete roadmap to a fault-tolerant machine. The company said it uses AI tools to organize program knowledge and to help coordinate research and fabrication across teams. The announcement prompted further discussion among technologists, security experts and cryptocurrency stakeholders about timelines and the need to migrate to quantum-resistant cryptographic methods.