Quantum Zeitgeist weekly digest, 27 September 2026

Logical qubits were the yardstick this week. Microsoft and Qolab published a definition of what makes a logical qubit scalable, and Infleqtion entangled 30 of them on its neutral-atom machine. IonQ showed that the classical decoding behind error correction can run on one ordinary CPU, removing a hardware bottleneck many had expected. Germany put money behind the same goal. It picked planqc and the LOGIQC consortium in its €640 million competition for error-corrected computers, and committed €122 million to a QUDORA-led project aiming for 50 logical qubits. IQM’s latest sales, in Brazil, Japan and a four-country European group, include staged upgrades toward logical operations in Finland. IonQ had the busiest week. Its Superion 256 is headed to NVIDIA’s research center, Florida International University and a new manufacturing site in South Korea. QuEra’s own survey found 45 percent of buyers now rank a fault-tolerance roadmap among their top criteria, though cost still comes first. Companies still count qubits, but buyers now want to know how many of them will be reliable. 1. Microsoft Quantum Defines Scalable Logical Qubit Characteristics Microsoft Quantum researchers, working with Qolab, have set out a definition of a scalable logical qubit. A logical qubit is one reliable…