Chinese scientists build ultra-precise clock they hope will help redefine the second
- Strontium-based optical clock loses or gains one second every 7 billion years
- China is just the second country after the US to achieve such precise timekeeping
A Chinese team has developed an extremely precise optical clock that loses or gains one second every 7 billion years, bringing scientists a step closer to redefining the second as a basic unit of time.
Using ultra-cold strontium atoms and powerful laser beams, the team at the University of Science and Technology of China created a clock with stability and uncertainty under 5 quintillionths.
The achievement makes China only the second country in the world after the US to achieve such precise timekeeping.
It also lays an important foundation for the establishment of a global optical clock network, the team, led by physicist Pan Jianwei, wrote in the peer-reviewed journal Metrologia earlier this month.
In addition, they said it opened up new pathways to test fundamental physics theories, detect gravitational waves and search for dark matter.
The current record holder for the most precise strontium-based optical clock is hosted at the University of Colorado in Boulder, developed by a group led by Chinese-American physicist Jun Ye. It remains slightly more accurate than its Chinese competitor and its operation is more stable.