Peking University has developed a rubidium atomic clock-an error of less than one second for three thousand years
Recently, the 203 Institute of the Second Academy of China Aerospace Science and Industry Corporation has led the research and development of an ultra-thin rubidium atomic clock with independent intellectual property rights. The research has been completed and mass production has been achieved. When the news came out, many friends became curious: What kind of clock is an atomic clock?
The clocks used in daily life, even if they are accurate, will have an error of tens of seconds in a year. The same is timekeeping, but the accuracy of atomic clocks is different. The elements currently used in atomic clocks include hydrogen, cesium, rubidium, etc. The most accurate atomic clock has an error of only 1 second every 30 million years. In other words, even if the dinosaurs went extinct to the present, its error was only two or three seconds. Among them, rubidium clocks are the most widely used atomic clocks. They are small in size, low in cost, reliable and environmentally adaptable, and can be widely used in weapons, telecommunications, electric power and other industries.
The ultra-thin rubidium clock developed by 203 is specially designed for board card use. A reporter from the Science and Technology Daily learned from the institute that many devices are currently designed with standardized card insertion methods. This modular design facilitates functional expansion and hardware replacement and maintenance, and has been used in various industries.
Since it is called a "board" card, it is conceivable that it will not be too thick. According to industry standards, the current board thickness is mostly 2 cm. In 2015, 203 Institute developed a small rubidium clock with high vibration resistance, the size is equivalent to a palm, but the thickness is close to 4 cm. The length and width of the ultra-thin rubidium clock are only 7.6 cm, and the thickness is compressed to 1.7 cm, which fully meets the requirements of the board.
However, it is not easy to achieve ultra-thin and meet performance requirements. There is a quantum system inside the ultra-thin rubidium clock, which is a physical component. There is a certain conflict between its size and performance indicators. To avoid performance loss while reducing the volume, a series of key technologies need to be overcome.
At the same time, the operating temperature of the internal components of the rubidium clock ranges from more than 80 degrees Celsius to more than 120 degrees Celsius. The integration of these high-temperature components in such a small space will inevitably affect each other, thereby affecting the product indicators and reliability, which affects thermal design and other technologies. It also brings high demands.
The ultra-thin rubidium clock product developed after successfully overcoming many problems has reached the international top level in technical indicators. For example, its built-in 1PPS taming function can receive signals from any navigation satellite to achieve the purpose of frequency calibration. In other words, as long as the navigation satellite signal in the sky can be received by the product receiver, it can reach the time accuracy of the navigation satellite, which is on the order of 20 nanoseconds.
Even if the navigation satellite signal is lost, the ultra-thin rubidium clock will automatically enter the hold state. The retention time accuracy depends on frequency stability and drift rate, and the product can maintain timekeeping accuracy on the order of microseconds for several days. The ability to keep time steadily is exactly the meaning of the existence of atomic clocks.
The application of atomic clocks has now penetrated into various fields.
In the movie, the SWAT officers will always get together with serious expressions and stretch their wrists to the watch in order to move together. But in the war, how do the various combat systems "match the table"? You have to rely on atomic clocks. With the development of modern warfare, accurate time systems have become the key to cyber operations. Once time is disrupted, the entire command system and weapon system will face paralysis.
The atomic clock is also inseparable in life. For example, in the communication field, communication base stations have a great demand for time synchronization. In the upcoming 5G era, this requirement will be more stringent. In the financial field, the atomic clock is one of the core devices to ensure the time consistency of the financial network. If there is a time difference in stock operations, someone may take the opportunity to conduct illegal transactions. In addition, the role of atomic clocks has become increasingly prominent in industries such as power and transportation.
At present, this ultra-thin rubidium clock has basically achieved the extreme size of rubidium clock products. According to the person in charge of the project, 203 Institute is developing a chip atomic clock with a new mechanism, which is smaller in size and lower in power consumption. The institute has now made engineering prototypes and plans to mass-produce in 2019.