Aalto University achieves millisecond coherence in transmon qubit, advancing quantum computing capabilities

Physicists from Aalto University in Finland have set a new world record by achieving millisecond coherence times in a superconducting transmon qubit, nearly doubling previous limits which were around 0.6 milliseconds. This breakthrough was published on July 8, 2025, in the peer-reviewed journal Nature Communications and represents a significant advance in quantum computing technology. Longer coherence times enable quantum computers to perform more complex operations reliably before errors accumulate, reducing the need for extensive error correction and paving the way toward more practical and scalable quantum processors. The team’s success was enabled by high-quality fabrication using superconducting films provided by Finland’s Technical Research Centre (VTT) and the use of state-of-the-art cleanroom facilities at Micronova, OtaNano. The work was conducted by the Quantum Computing and Devices research group under Professor Mikko Möttönen and led by PhD student Mikko Tuokkola, with supervision from postdoctoral researcher Dr. Yoshiki Sunada. This achievement not only strengthens Finland’s position at the forefront of quantum technology research but also highlights reproducibility by sharing detailed methods freely with the global scientific community. Future quantum scaling challenges such as noise reduction and qubit count increases are being targeted by expanding the research team with new senior and postdoctoral positions. This milestone opens new possibilities for advanced quantum computations and contributes critically to the pursuit of fault-tolerant quantum computing.