Insider’s memory
- Google Quantum AI’s new 105-qubit Willow chip marks a new milestone in quantum computing for the enterprise, demonstrating enhanced computing power, scalable error correction, and a path to commercially viable systems.
- In a benchmark test, Willow performed a calculation in minutes that would take the fastest classical supercomputer an astronomical amount of time, illustrating quantum’s exponential advantage over classical computing.
- By showing that increasing the number of qubits can actually reduce errors, the Willow chip validates a fundamental approach to quantum error correction, paving the way for large-scale, fault-tolerant quantum machines capable of overcoming the challenges of the real world.
Google Quantum AI announced that it is moving beyond the Sycamore era and taking the next step in its roadmap with the introduction of the 105-qubit Willow, a new quantum chip that has reached a significant milestone in terms of computing power and error correction, marking a major step toward large-scale and commercially viable quantum computing.
The team, which published its findings in Naturealso envisions a quantum device that overcomes the limitations of errors and offers real-world solutions to difficult problems, the ultimate destination as they progress on their roadmap.
“The mission of the Google Quantum AI team is to develop quantum computing to solve otherwise intractable problems,” said Hartmut Neven, vice president of engineering at Google and founder and director of the Quantum AI Lab. quantum artificial intelligence, during a recent round table on this new stage. . “So what problems do we have in mind?” The first applications will be the modeling and understanding of systems where quantum effects are important. So it is the case of joint drug discovery, understanding and design of nuclear fusion reactors, thereby reducing the enormous energy costs associated with fertilizer production. But this then extends to several other areas, such as quantum machine learning.
Exponential advantage over traditional supercomputers
In a benchmark test using random circuit sampling (RCS), the new chip completed a calculation in about five minutes, which would take the world’s fastest conventional supercomputer, Frontier, about 10 seven billion years, even longer than the age of the universe. This result highlights the growing gap between quantum and classical computing as quantum systems develop.
Random sampling of circuits is widely used to measure whether a quantum computer can perform calculations beyond the capabilities of classical systems. The latest results, which improve on similar tests carried out in 2019 and 2024, demonstrate the exponential speedup of quantum processors as they increase in power.
The comparison with Frontier was done conservatively, assuming ideal performance compared to the classic system. The researchers suggest that the growing gap between classical and quantum computers means that even as classical computers improve, the gap will continue to widen exponentially.
Error correction milestone
Quantum error correction, the cornerstone of reliable quantum computing, has also seen significant progress. Errors, a persistent challenge in quantum systems due to their fragile nature, traditionally increase as the number of qubits increases. However, the new chip demonstrated the opposite: as more qubits were added, error rates decreased exponentially.
“Quantum information is extremely fragile. It can be disrupted by many factors ranging from microscopic defects in materials to ionizing radiation to cosmic rays,” said Michael Newman, research scientist at Google Quantum AI.
Newman said their approach is to implement error correction by making physical qubits work together to correct errors, which is usually called creating a logical qubit.
“The basic idea is that you take many physical qubits and make them work together to represent a single — what we would call — a logical qubit,” Newman said. “So there may be tons of physical qubits, but there may only be three logical qubits, so these qubits are all working together to correct errors, and the hope is that as you grow these collections , there will be more and more of them. So your qubits are getting more and more precise. The problem, of course, is that as these things get bigger, there are also more. possibilities of error and we So we need devices that are good enough that as we scale things up, the error correction overcomes these additional errors being introduced back into the system.
In the study, the researchers showed that moving from a 3×3 grid to 5×5 and then to 7×7 grids of physical qubits reduced errors by a factor of two each time.
According to the team, this achievement addresses a challenge that has hampered progress since quantum error correction was first proposed in 1994. Ultimately, they plan to continue working to improve this system – as well as implementing more new techniques and algorithmic innovations – to move ever closer to the ultimate goal: a fault-tolerant quantum computer.
The results confirm the feasibility of building error-resilient large-scale quantum systems, paving the way for practical quantum applications.
“Error correction is the end game for quantum computers,” said Julian Kelly, director of quantum hardware at Google Quantum AI. “It’s the quantum computer that everyone imagines using, running really big problems and getting interesting applications.”
He added: “Willow was designed with scalable error correction in mind. It’s not just for this demonstration, but it’s a technology that can take us into the future.
State-of-the-art manufacturing and measurement
The chip, comprising 105 qubits, was produced in a factory dedicated to the manufacture of superconducting quantum chips in Santa Barbara. Designed for optimal performance, it integrates error correction into every aspect of its architecture, from gate development to calibration and manufacturing.
Its performance spans several criteria, reflecting a holistic approach to the design of quantum systems. The chip demonstrates advancements not only in raw computing power, but also in system-wide efficiency and adaptability.
Commercial Potential
The chip’s capabilities represent a step closer to realizing quantum systems capable of solving real-world problems. These systems have potential for application in drug discovery, materials science, and renewable energy technologies, including designing efficient electric vehicle batteries and accelerating progress in nuclear fusion. Many of these tasks are currently infeasible on classical systems, until quantum systems can unlock computing power.
Google also provides insight into its marketing strategy.
While some companies are exploring commercialization and technical improvements simultaneously — for example, selling units on-premises or providing access to the quantum device over the cloud — Google appears to want to first perfect the technology and then determine how best to TO DO. quantum money.
The team did not specify – wisely – when exactly it hoped to reach this quantum advantage inflection point, saying there were challenges ahead.
They write in a company blog post: “At current physical error rates, we may need more than a thousand physical qubits per surface code grid to achieve relatively modest coded error rates from 10-6. Additionally, all of this was done on a 105-qubit processor; can we obtain the same performance on a 1000 qubit processor? What about a million-qubit processor? The technical challenge that awaits us is immense. At the same time, the progress has been astounding and the improvement offered by quantum error correction is exponential. We’ve seen a 20x increase in coded performance since last year: how many more 20x steps before we can run quantum algorithms at scale? Maybe less than you think.
What’s next
The new chip’s achievements in computing power and error correction accelerate progress toward the long-term goal of large-scale, error-correcting quantum computers. Researchers are optimistic that such systems will unlock transformative applications across industries. As quantum technology continues to evolve, the gap between classical and quantum systems is expected to widen, making this revolutionary technology increasingly practical and impactful.
Charina Chou, Director and COO of Google Quantum AI, said: “We are very interested in offering a quantum computing service that can solve real-world problems that would not otherwise be possible on classical computers. »