According to the University of Science and Technology of China, a research team composed of Pan Jianwei, Chen Yuao, Dai Hanning, etc. has successfully developed a strontium atomic optical lattice clock with stability and uncertainty better than 5 10-18 per 10,000 seconds (equivalent to an error of no more than one second in billions of years).
At present, the system is not only the best optical clock for the current domestic comprehensive indicators, but also makes China the second country to reach the above comprehensive indicators, the first is the United States. However, our country has surpassed the United States in some respects.
According to public information, in January 2014, the United States was jointly launched by the National Institute of Standards and Technology (NIST) and JILA to launch the most accurate strontium atomic optical lattice clock in time, which only produces a 1 second error in 5 billion years.
In terms of error, in fact, China has surpassed the United States.
Strontium atomic optical lattice clock is a type of atomic clock based on strontium (sr) atoms, also known as optical lattice clocks. An atomic clock is a device that measures time with a high degree of accuracy. While traditional atomic clocks utilize cesium atoms in cesium (CS) or gas discharge tubes for measurements, strontium atomic optical lattice clocks use the ultra-fine structure of strontium atoms to achieve greater accuracy.
Strontium atom optical lattice clocks are based on ultracold Bose-Einstein condensates that cool strontium atoms to a few microkelvins at low temperatures. Then, the atoms are trapped in the optical lattice by laser cooling technology to form a precise three-dimensional optical potential trap. This optical potential well can effectively isolate atoms, reduce the interaction between atoms and the outside world, and improve the stability and accuracy of the clock.
Strontium atom optical lattice clocks use the resonance frequency of the ultrafine structure of strontium atoms as a reference for time. Superfine structure refers to the interaction between the spin of the nucleus and the movement of electrons inside an atom. By measuring these resonant frequencies, the strontium atomic optical lattice clock is able to provide a very accurate time signal. It has been reported that the accuracy of the strontium atomic optical lattice clock reaches the level of 100 million years per second.
The high accuracy and stability of the strontium atomic optical lattice clock make it have a wide range of application prospects in the fields of scientific research, navigation systems, communication and satellite positioning.
1.Time Measurement Standards: As highly accurate time measurement devices, strontium atomic optical lattice clocks can provide accurate time benchmarks for other clocks and time measurement devices. Its accuracy is usually measured in nanoseconds (10 -9 seconds) or picoseconds (10 -12 seconds), making it an important tool in modern metrology.
2.Scientific research: Strontium atomic optical lattice clocks play an important role in basic scientific research. It is used in laboratory research to explore topics such as gravity, relativistic effects, cosmology, and fundamental physical constants. By measuring extremely accurate time signals, scientists are able to validate theoretical models, check the stability of physical constants, and provide more accurate experimental data.
3.Navigation and positioning: Precise time synchronization is essential for navigation and positioning systems. Strontium atomic optical lattice clocks can provide high-precision time signals, which can be applied to satellite navigation and precision positioning technology. By ensuring time synchronization between different systems, the performance and accuracy of navigation equipment can be greatly improved, especially for applications that require high accuracy, such as aerial navigation, satellite positioning, and mapping.
4.Communication and networking: In a global communications network, it is important to ensure that the time synchronization of the various nodes is carried out. Strontium atomic optical lattice clocks can provide very accurate clock signals for synchronizing the operation of various communication nodes. This is critical to ensure accurate data transmission, increase network throughput, and reduce signal interference.
5.Other areas of application: The high accuracy and stability of strontium atomic optical lattice clocks also have the potential for a wide range of applications. For example, it can be used to achieve more accurate timestamps to improve the speed and accuracy of financial transactions. In addition, strontium atomic optical lattice clocks can also be used in laboratory research, astronomical observations, precision measurements and other fields to promote technological progress and innovation.
Strontium atomic optical lattice clocks are not only one of the most accurate devices in the field of time measurement, but also play an important role in scientific research, navigation and positioning, communication networks and other fields. Its high accuracy and stability provide a reliable time reference for a variety of applications, driving the development of related technologies and a wide range of applications.