IQM has announced that its barbell code is capable of reducing logic error rates by up to 1,000 times compared to the commonly used surface code, while only requiring a physical qubit count of 1/8. The development process and effectiveness analysis of the code were published on the arXiv database this month.
According to CNBC, quantum computers utilize the laws of quantum mechanics to solve problems that are too complex for traditional computers, which store information in the form of bits (0 and 1). In contrast, quantum computers use quantum bits or qubits, which can be 0, 1, or any value in between. They can handle much larger volumes of data, driving breakthroughs in fields such as medicine, science, and finance.
However, quantum computers are fragile and prone to errors, making them not yet useful or practical. Error correction is considered one of the main challenges that allows them to address commercially valuable problems on a large scale.
Researchers employ quantum error correction techniques—distributing information across multiple physical qubits to create more reliable logical qubits. However, current methods often require a large number of qubits and complex hardware. According to IQM, the barbell code aims to improve both efficiency and practicality by reducing error rates while also decreasing the number of physical qubits required to protect quantum information.
The barbell code is specifically designed for IQM’s Constellation processor architecture, which features enhanced connectivity between qubits. In this system, each qubit can interact directly with up to 12 neighboring qubits, compared to only 4 qubits in traditional square lattice structures.
The company stated that this design enables effective error correction without the need for additional complex hardware. The Barbell code uses a long coupling link for every second qubit, reducing the need for multiple long-range coupling links that can complicate the chip fabrication process. By leveraging the processor’s connectivity, the new code can create the quantum entanglement necessary for error correction while keeping hardware requirements relatively low.
IQM Quantum Computers’ quantum computer in an exhibition in Finland in February 2026. Photo: IQM Quantum Computers
IQM stated that the new method focuses on practical superconducting quantum processors rather than idealized laboratory systems. “We are pioneering the next chapter in quantum computing. The new approach provides a highly competitive roadmap for scaling quantum error correction with superconducting qubits, paving the way for large-scale fault-tolerant quantum computers,” said Jan Goetz, co-founder and CEO of IQM.
The barbell code was announced as IQM prepares to deploy 150-qubit quantum systems for customers by the end of this year. Earlier, the company also introduced the IQM Halocene, a quantum computer designed for testing and developing error correction technology.
Last year, at Nvidia’s GTC Paris developer conference, CEO Jensen Huang stated that quantum computing is reaching a turning point. He remarked that the quantum computing technology that companies have developed over decades will soon yield success as systems rapidly become “more powerful, more efficient, and more resilient.”
Thu Thao summarized.
