According to reports, Chinese scientists at the University of Science and Technology of China have created an optical clock with previously unheard-of accuracy and stability—less than five quintillionths of a second. This amazing clock represents a major advancement in the field of atomic clocks, with a projected gain or loss of only one second over the next seven billion years.
With potential uses in improving quantum key distribution and fine-tuning global positioning systems (GPS), optical clocks are essential to the rapidly changing field of technology. China is now the second country in the world to demonstrate such accurate timekeeping skills, after research teams from Germany, the US, and Japan have been working hard to advance atomic clock technology.
Conventionally, cesium atoms and microwave pulses are used in atomic clocks, such the famous microwave fountain clock at the University of Colorado in Boulder, to ensure accurate timekeeping. China’s optical clock, on the other hand, uses laser light rather than microwaves, which could result in a two-fold increase in performance.
Led by Pan Jianwei, the Chinese research team utilized strontium atoms in their optical clock. By cooling down the strontium atoms to temperatures of a few micro-Kelvin and trapping them in a one-dimensional lattice created by intersecting laser beams, the researchers achieved a clock transition that was both stable and precise.
Comparisons with other independent clocks verified the optical clock’s stability to 2.2 quintillionths and uncertainty to 4.4 quintillionths. According to the researchers, the clock is expected to deviate by just one second in 7.2 billion years, meeting the stringent criteria for future adoption of optical clocks in precise timekeeping.
Beyond its timekeeping applications, the research team envisions using different atoms, such as ytterbium, to further explore and understand variations in timekeeping. Moreover, the researchers believe their work has opened avenues for testing fundamental theories in physics, as well as searching for gravitational waves and dark matter. As China takes a significant stride in the realm of atomic timekeeping, the implications for scientific advancements and technological innovations are vast and promising.