Chinese Researchers Develop Highly Precise Optical Clock That Could Redefine the Second
Scientists in China have recently unveiled a groundbreaking achievement in timekeeping technology with the creation of an incredibly precise optical lattice clock. This innovative clock has the capability to measure time to an unprecedented 19 decimal places, making it one of the most accurate timekeeping devices ever developed.
Unlike traditional clocks that rely on mechanical mechanisms, the strontium optical lattice clock operates based on the oscillations of strontium atoms at visible light frequencies. This allows the clock to produce an astonishing 700 quadrillion ‘ticks’ per second, far surpassing the accuracy of conventional atomic clocks.
The significance of this advancement lies in the potential to redefine the standard unit of time – the second. Currently, the second is defined as a fraction of a day, which poses challenges due to the Earth’s variable rotation speed. By using atomic clocks like the strontium optical lattice clock, scientists can measure time based on the unchanging properties of atoms, leading to a more precise and stable definition of the second.
According to a recent study published by researchers at the University of Science and Technology of China (USTC), the upgraded strontium optical clock has achieved an uncertainty of 9.2 x 10^-19 and a stability of 6.3 x 10^-19. These results meet the accuracy requirements necessary for redefining the SI second, paving the way for potential applications in areas such as relativistic geodesy and dark matter research.
With several other optical clocks reaching similar levels of precision, the scientific community is moving closer to the goal of officially redefining the second. However, this decision is subject to approval by the General Conference on Weights and Measures (CGPM), which convenes every four years to address standard unit definitions. While the criteria for redefinition may not be met at the upcoming CGPM meeting in October, progress is being made towards presenting a proposal by the 29th meeting in 2030.
The potential implications of redefining the second go beyond precision timekeeping, with applications in fundamental scientific research and technological advancements. As optical clocks continue to push the boundaries of time measurement, we are on the brink of a new era in timekeeping accuracy that could revolutionize various fields of study.
For more information on the USTC’s optical clock research, you can refer to the published paper in the journal Metrologia.
