Google makes quantum computing breakthrough with new Willow chip

Google has introduced the superconducting Willow quantum chip designed to solve complex computational problems in less than five minutes.

The tech giant claims the state-of-the-art invention could eventually supersede the problem-solving capability of today’s fastest supercomputers, which are more likely to take up to 10 septillion — or 10 to the power of 25 — years to solve the same problems.

The mind-boggling number exceeds known timescales in physics and vastly exceeds the age of the universe.

Quantum error correction

Willow’s value lies in the 105 qubits, or units of computation, used in its fabrication and the qualitative change which results from integrating quantum error correction.

Errors are one of the greatest challenges in quantum computing as qubits have a tendency to rapidly exchange information with their environment, making it difficult to protect the information needed to complete a computation.

Typically, the more qubits used, the more errors will occur and the system becomes classical.

Willow is reportedly the first processor where error-corrected qubits get exponentially better as they get bigger.

Significant leap

Google Quantum AI head Hartmut Neven said the Willow chip represented a significant leap forward in quantum hardware.

“When I founded Google AI in 2012, the vision was to build a useful, large-scale quantum computer that could harness quantum mechanics […] to benefit society by advancing scientific discovery, developing helpful applications and tackling some of society’s greatest challenges,” he said.

“Our Google Research team has charted a long-term roadmap and Willow moves us significantly along that path towards commercially relevant applications.”

Qubit testing

Testing of progressively larger arrays of physical qubits showed a connection between the number used in Willow and a reduction in quantum errors.

“Each time, using our latest advances in quantum error correction, we were able to cut the error rate in half to ultimately achieve an exponential reduction,” Mr Neven said.

“The more qubits we use in Willow, the more we reduce errors and the more quantum the system becomes.”

The accomplishment is known in the field as “below threshold,” or being able to drive errors down while scaling up the number of qubits.

“This has been an outstanding challenge since the concept of quantum error correction was first introduced in 1995,” Mr Neven said.

Largely experimental

Experts say Willow is, for now, a largely experimental device.

This is mainly because a quantum computer powerful enough to solve a wide range of real-world problems is still years — and billions of dollars — in the making.

Nevertheless, Mr Neven said the achievement was a major step forward in a journey that began more than a decade ago.

“Quantum computation will become indispensable for a number of tasks such as collecting training data that is inaccessible to classical machines, training and optimising certain learning architectures and modelling systems,” he said.

“This includes helping us discover new medicines, designing more efficient batteries for electric cars and accelerating progress in fusion and new energy alternatives.”