July 15, 2024 A major breakthrough in quantum computing has been achieved by Quantinuum, which has developed a 56-qubit H2-1 quantum computer that surpasses Google’s 2019 quantum supremacy record by 100-fold. Quantinuum’s computer has set a new standard by achieving an error correction performance threshold that many believed was years away.
In 2019, Google announced that its Sycamore quantum computer completed a complex computation in 200 seconds, a task that would have taken the world’s fastest classical supercomputer, Summit, approximately 10,000 years to finish. This achievement was a significant milestone in quantum computing, known as quantum supremacy. Despite some controversy, including IBM’s claim that the task could be performed in 2.5 days on a classical system, Google’s claim has largely held.
Quantinuum has now raised the bar significantly. Between January and June 2024, the company conducted multiple experiments and demonstrated a performance that eclipses Google’s previous record. The company achieved a linear cross-entropy benchmark (XEB) score of ~0.35, more than 100 times better than Google’s result of ~0.002. This advancement is largely attributed to the company’s sophisticated error correction methods.
Quantinuum’s H2-1 quantum computer, configured with 32 physical qubits, created four highly reliable logical qubits that operate at “better than break-even” performance. This is a crucial step towards fault-tolerant quantum computing, where logical qubits are more reliable than the physical qubits they are composed of. The logical circuit error rates were up to 800 times lower than the corresponding physical circuit error rates, an achievement unmatched by any other quantum computing company.
Error correction is essential for practical quantum computing, allowing for longer and more complex calculations by protecting quantum information from noise and decoherence. Current state-of-the-art quantum computers typically have error rates ranging from 1% to 0.1%, making Quantinuum’s advancements particularly notable.
Ilyas Khan, founder and Chief Product Officer of Quantinuum, acknowledged the significance of Google’s 2019 achievement and emphasized that their new work represents a monumental step forward. “We now operate in a place that has been anticipated for so long, where classical supercomputers simply cannot compete,” Khan said.
Quantinuum’s research has been published in a study on the preprint database arXiv, though it has not yet undergone peer review. This new milestone signals a transformative era in quantum computing, with implications for a wide range of applications from cryptography to complex simulations.
