New quantum code cuts error rates by 1,000x while using up to 8x fewer qubits New quantum error-correcting code claims 1,000x lower error rates and up to eight times fewer qubits. IQM Quantum Computers has developed a new quantum error-correcting code that it says can reduce logical error rates by up to 1,000 times compared with the widely used surface code while requiring up to eight times fewer physical qubits. The company said the new approach, called barbell codes, could help address one of the biggest challenges facing quantum computing: correcting errors quickly enough to enable large-scale, fault-tolerant machines. Quantum computers are highly sensitive to noise, which can introduce errors during calculations. To overcome this, researchers use quantum error correction, a process that spreads information across multiple physical qubits to create more reliable logical qubits. However, existing methods often require large numbers of qubits and increasingly complex hardware. According to IQM, its new code aims to improve both efficiency and practicality by lowering error rates while reducing the number of physical qubits needed to protect quantum information. Fewer qubits, fewer errors The barbell code family was designed specifically for IQM’s Constellation processor architecture, which features enhanced connectivity between qubits. In the system, each qubit can directly interact with up to 12 neighboring qubits, compared with four in a conventional square-grid arrangement. The company said the design allows high-performance error correction without requiring extensive additional hardware. Barbell codes rely on a single long coupler connection for every second qubit, reducing the need for multiple long-range crossing couplers that can complicate chip fabrication. By taking advantage of the processor’s connectivity, the code can generate the entanglement needed for error correction while keeping hardware requirements comparatively low. “We are pioneering the next chapter in quantum computing,” said Jan Goetz, CEO and Co-founder of