Quantinuum, the world's largest integrated quantum computing company, together with Microsoft(MS), has achieved a breakthrough in making fault tolerant quantum computing a reality, by demonstrating the most reliable logical qubits with active syndrome extraction, an achievement previously believed to be years away from realization.

A collaboration between Quantinuum's team in the USA and UK and Microsoft's quantum computing team has led to the creation of four logical qubits that demonstrate error rates 800 times lower than corresponding physical error rates. 

Impressively, the joint team demonstrated the ability to run 14,000 independent instances of a quantum circuit error-free.

Breakthroughs of this magnitude have the potential to significantly accelerate progress towards the ultimate goal of achieving universal fault tolerant quantum computing, potentially shortening the timeline to tackling real-world problems and revolutionizing fields like materials science and drug discovery.

The achievement stems from the industry leading fidelity, scalability, and flexibility of Quantinuum's 32-qubit H2 quantum processor, Powered by Honeywell, combined with Microsoft's highly innovative error correction capabilities. 

The joint team created four logical qubits using 30 of the 32 physical qubits available on the H2, leading to the creation of what both companies herald as the most "reliable logical qubits". They also successfully demonstrated syndrome extraction, another critical milestone that is necessary for fault tolerant quantum computing. 

"The result announced today further cements Quantinuum's position at the forefront of universal fault tolerant quantum computing. Today's achievement was only possible using Quantinuum's H2 quantum computer, with its unparalleled 99.8% two-qubit gate fidelities; the 32 qubits in our QCCD architecture; and all-to-all qubit connectivity," said Rajeeb Hazra, CEO, Quantinuum.

"Building on the exceptional performance of our current systems, we will continue to innovate to make universal fault tolerant quantum computing a reality sooner than previously imagined."

In the new era described by Microsoft as "Level 2 Resilient", quantum computing is capable of dealing with the issues caused by errors, and can begin to tackle meaningful challenges, such as modelling the states of molecules and materials, simulating systems in condensed matter physics, and exploring solutions to problems across many fields. 

Based on Microsoft's exacting criteria, the demonstration of multiple, entangled logical qubits, with the logical qubits outperforming the physical qubits marks a long-anticipated transition into this second phase of quantum computing.