Microsoft and Quantinuum demonstrate four highly reliable logical qubits

Microsoft Quantum

Microsoft and Quantinuum achieved logical error rates 800 times lower than physical qubits—the largest gap reported to date—by combining Microsoft's qubit virtualization and error-correction system with Quantinuum's trapped-ion hardware. The system successfully ran more than 14,000 individual experiments without error, advancing quantum computing from the NISQ era to Level 2 (Resilient) capability.

• Error rate 800× better than physical qubits; first four-logical-qubit system demonstrating such improvement.
• Completed 14,000+ experiments without a single logical error; system diagnoses and corrects errors without destroying qubits—a capability called active syndrome extraction.
• Transition from Level 1 (Foundational, current NISQ era) to Level 2 (Resilient) quantum computing, enabling practical error correction at scale.