Google Quantum AI announced on October 15, 2026 that it has demonstrated "magic state cultivation" working in practice on its Willow quantum processor, reducing errors about 40-fold compared with running without it. The work is published in Science. The announcement page carries a date without a time of day. Read the announcement.
Why it matters
Universal quantum computers need more than the error-corrected operations a surface code provides: certain non-Clifford operations, supplied by special "magic" quantum states, are required to run useful programs. Researchers have foreseen this bottleneck since 2004, long before quantum computing became a practical engineering pursuit. Producing high-quality magic states at scale — cultivation — has been one of the key obstacles to scaling quantum machines to practical use.
What Google reports
The Google Quantum AI team, including research scientist Emma Rosenfeld and software engineer Craig Gidney, reports that cultivation works on the Willow hardware in practice, with the roughly 40-fold error reduction measured against operating without the technique. The company describes the result, published in Science, as a crucial step toward scaling quantum computing to practical use.
The announcement is a vendor research milestone; the underlying claims appear in the peer-reviewed Science publication. For how we treat research announcements, see our verification guide.