Google Quantum Chip Significantly Reduces Computing Time

Google announced its latest quantum chip Willow can perform computing functions in a fraction of the time a traditional machine would take. The search giant said it also delivers an exponential reduction in errors.

Hartmut Neven, founder and lead of Google Quantum AI, blogged about Willow’s accomplishment in performing a standard benchmark computation in less than five minutes, explaining this would take even the fastest current machines 10 septillion years. The time a machine of today would take vastly exceeds the age of the universe, Neven wrote. He explained Willow provides a significant advance in Google’s goal to build a useful, large-scale quantum computer, a journey that commenced in 2012.

The benchmark involved was random circuit sampling, a process other Google researchers have previously explained offers some small guarantees regarding computational abilities by comparing quantum processors with the most cutting-edge machines of today. Neven wrote the approach is the classically hardest benchmark a quantum computer can currently run. “You can think of this as an entry point for quantum computing, it checks whether a quantum computer is doing something that couldn’t be done on a classical computer,” Neven added Google’s work with one of the most powerful classic supercomputers shows the gap between their capabilities and quantum processors is growing at a double exponential rate.

The reduction in errors is an important element in the Willow benchmark. Neven explained the qubit unit of computation power employed in quantum machines is prone to errors due to the speed with which information is exchanged. In a related article, Google specialists explained they upped the correctional capabilities of Willow by grouping qubits into a surface that is more tolerant of errors. The bigger the surface gets, the greater its ability to resist errors.

Neven explained the Willow test began with a surface of 3×3 encoded qubits, which it increased in stages to a size of 7×7 and, in turn, cut the error rate in half. “This historic accomplishment is known in the field as below threshold, being able to drive errors down while scaling up the number of qubits. You must demonstrate being below the threshold to show real progress on error correction”.

Neven noted other firsts in the Willow test involving real-time error correction on a superconducting quantum system and the fact it was beyond breakeven because its qubit arrays have longer lifetimes than individual units, an unfakeable sign that error correction is improving the system overall. The Google engineer told BBC News it was unlikely a commercial quantum chip would be released before the end of the decade. Other specialists offered a dose of realism over the company’s latest achievement, pointing out it involved a single, specialized test.