According to The Harvard Gazette, qubits keep slipping out of their quantum states, which trashes the information they hold. The new paper claims that a team built complex circuits stuffed with dozens of error-correction layers that suppress errors below the critical threshold, where every extra qubit makes things worse.

Harvard Quantum Science and Engineering Initiative co-director and senior author Mikhail Lukin said: “For the first time, we combined all essential elements for a scalable, error-corrected quantum computation in an integrated architecture. These experiments, by several measures the most advanced that have been done on any quantum platform to date, create the scientific foundation for practical large-scale quantum computation.”

Lead author Dolev Bluvstein said: “There are still a lot of technical challenges remaining to get to a very large-scale computer with millions of qubits, but this is the first time we have a conceptually scalable architecture. It’s going to take a lot of effort and technical development, but it’s becoming clear that we can build fault-tolerant quantum computers."

Google Quantum AI vice president of engineering Hartmut Neven said the work landed in the middle of an “incredibly exciting” race between qubit platforms.

“This work represents a significant advance toward our shared goal of building a large-scale, useful quantum computer”, he said.

Lukin said the pieces for proper machines are finally lining up and added, “This big dream that many of us had for several decades, for the first time, is really in direct sight.”

The Gazette pointed out that a system with 300 quantum bits can store more information than the number of particles in the known universe. The new paper is part of a 30-year slog to make quantum error correction work, and no potentially dead-or-alive cats were harmed during the discovery.