Researchers have created an atomic clock that can be taken into war zones, and it could change the future of military combat. — SCMP
A timepiece that could profoundly change the nature of future warfare has been created by Chinese scientists.
Standing 1.5 metres (4.9 feet) tall and roughly the size of a single-door refrigerator, the caesium atomic fountain clock can be loaded onto a military truck and, after enduring long-distance transport with bumpy roads and other harsh environments, it can still cap the uncertainty of its timekeeping to less than one-fifth to the quadrillionth of a second.
This feat was once deemed impossible, as only the atomic clocks that set international standard time can achieve this precision, and those clocks are all large and need to be housed in a guarded laboratory against all environmental disturbances.
A high-precision timekeeping system is the backbone of modern warfare, enabling radars separated by thousands of miles to operate in unison, as they detect and track elusive stealth fighters. It also improves the quality of signals in electronic warfare and facilitates the transmission of vast amounts of data.
Extremely accurate timekeeping machines can even help turn science fiction into reality, such as combining lasers or microwaves emitted by different combat platforms into a single deadly beam to destroy enemies with tremendous energy.
The NIM-TF3 atomic clock, manufactured by the National Institute of Metrology of China, can operate autonomously for long periods without the need for professional maintenance, making it highly suitable for open-world applications.
In a peer-reviewed paper published in the Chinese-language Metrology Journal on December 18, the project team, led by Professor Lin Pingwei, said that the clock’s long-term stability reached an astonishing level of five quadrillionths in actual tests.
This is two orders of magnitude higher in performance compared to the best mobile atomic clocks currently available in the United States. It gives the People’s Liberation Army (PLA) a significant advantage in the arms race with the US military in electronic warfare, directed energy weapons and unmanned technologies.
Caesium atomic clocks work like fountains. Scientists first cool caesium atoms using lasers and then shoot them straight up into the air. The atoms fall under gravity and emit fluorescence as they pass through a microwave energy field. By counting these flashes, scientists can obtain an extremely precise reference time.
The recognised length of a second worldwide is defined by caesium atomic clocks. However, these devices are not only complex and expensive, but also require frequent maintenance and are highly susceptible to external environments, such as vibration and magnetic disturbances.
To overcome these challenges, Lin and his colleagues made numerous innovations. For example, they overhauled the design of a top-mounted ion pump that had been used by scientists worldwide for decades, moving the pump to the middle section of the clock. It significantly reduced the system’s volume and improved its performance.
They also invested considerable time and effort in rewriting the underlying machine code in assembly language, a type of computer coding method that is now mostly forgotten, to improve the system’s overall efficiency and reliability.
The United States and China are engaged in a fierce competition in high-precision timekeeping technology. The most precise atomic clock on Earth is still in the United States, but it was built by a team led by Chinese researchers. Some of these scientists, under geopolitical pressure, are considering returning to China.
At the same time, China is rapidly closing the gap with the United States and has surpassed it in some key areas. For example, the atomic clocks on BeiDou satellites now outperform those on GPS satellites.
The hydrogen atomic clock on the Chinese space station has broken the record for timekeeping accuracy in space, and the longest and most precise time-synchronised fibre-optic network in the world was also up and running in mainland China last year. – South China Morning Post
