What just happened? In 2019, Google’s Sycamore quantum computer achieved what’s known as quantum supremacy, completing a certain task in 200 seconds that would have taken a classical supercomputer 10,000 years. There’s been some controversy over the achievement, but Google’s claims have generally stood the test of time. Until now. Last month, a company called Quantinuum announced that it had reached a threshold of error-correction performance that many thought was years away.
The new 56-qubit H2-1 computer beats the “quantum supremacy” record set by Google’s Sycamore quantum computer by 100 times.
That title now belongs to a computing company. It is called Quantinium conducted multiple experiments with its quantum computer between January and June 2024. The company claims that its machine achieved a threshold of error-correction performance that many experts thought was still years away.
The company published its findings last month in a study uploaded to a preprint database. arXivThis study Peer reviewed still.
Quantinuum claims to have demonstrated significant performance improvements through the use of a random circuit sampling algorithm, resulting in an estimated Linear Cross Entropy Benchmark (XEB) score of approximately 0.35, an improvement of over 100x over previous demonstrations.
Comprised of 32 physical qubits, H2-1 supports the creation of four reliable logical qubits that operate at “above breakeven” performance, representing a major step towards fault-tolerant quantum computing, according to Quantinuum — that is, logical qubits are more reliable than the physical qubits that make them up, a critical threshold for practical quantum error correction.
The logic circuits have also been shown to have error rates up to 800 times lower than the error rates of their physical counterparts, which Quantinuum says no other quantum computing company has found anything comparable.
error Fixes Quantum computers can perform longer and more complex calculations by protecting quantum information from noise and decoherence. In quantum computing, error rates are typically much higher than in classical computing, with current state-of-the-art quantum computers having error rates in the range of 1% to 0.1%.
Google’s Sycamore quantum computer has 53 qubits and was first introduced in 2019. completion Complete a specific task in 200 seconds registerThe XEB result for g was about 0.002. Google claimed that even Summit, the world’s most advanced classical supercomputer, would take about 10,000 years to complete the task.
In other words, IBM has achieved a significant milestone in quantum computing: quantum supremacy. task A traditional system like Summit takes just 2.5 days.
But Quantinum founder and chief product officer Ilyas Khan seemed to acknowledge Sycamore’s work: “When Google announced details of its ‘quantum supremacy’ experiment in late 2019, the company’s CEO Sundar Pichai published a blog that has stood the test of time about the significance of the milestone achieved at the time,” he said.
Quantinuum’s work “raises that bar and clearly demonstrates that we are operating in areas long anticipated: areas where traditional supercomputers cannot compete, where the computational tasks are measurable and relevant.”
