Scientists Unveil World's First Functional Nuclear Clocks in Breakthrough Physics Study

Scientists from Europe and China have achieved a significant milestone by successfully operating the world’s first nuclear clocks. The breakthrough, detailed in separate papers published in Nature on October 7, 2026, represents a major leap forward for timekeeping technology.

The European team was led by Thorsten Schumm of Vienna University of Technology and Ekkehard Peik from PTB, Germany's National Metrology Institute, while the Chinese team was headed by Shiqian Ding from Tsinghua University. These researchers have developed nuclear clocks that measure time based on energy transitions within atomic nuclei instead of electron transitions in traditional atomic clocks.

Nuclear clocks offer a more stable and precise method for measuring time due to their reduced susceptibility to external disturbances compared to optical atomic clocks. The key challenge has been identifying the right element with suitable nuclear properties. After extensive research, scientists settled on thorium-229 because of its unique low-energy excited state that can be manipulated using laser light.

The breakthrough came in 2024 when researchers first demonstrated the ability to drive this transition and measure it accurately. However, stabilizing a laser to this nuclear transition remained an obstacle until both teams independently solved the problem around the same time. The European team used lower-powered lasers with more thorium nuclei, while the Chinese team employed higher-powered lasers interacting with fewer atoms.

Despite their initial success, these early nuclear clocks are currently less stable than existing atomic clocks. They accumulate roughly one second of timing error over millions of years compared to billions for today’s best conventional clocks. Nonetheless, researchers believe that further refinements could significantly improve performance and practical applications.

Potential uses for nuclear clocks include enhancing timekeeping precision in various fields such as navigation systems and telecommunications networks. Additionally, these devices may aid in fundamental physics research, particularly in the search for dark matter. The European team is already applying its technology to this area of study.

The development of nuclear clock technology holds promise not only for advancing scientific understanding but also for practical applications that rely on extremely precise timekeeping. As researchers continue to refine and improve these devices, they could lead to significant advancements across multiple disciplines in the coming years.