Yuan-Yu Jau, a senior investigator at Sandia National Lab, wants to build the world’s smallest atomic clock.
If he succeeds, he and his team at Sandia National Laboratories will make an atomic clock smaller than a sugar cube.
The Defense Advanced Research Projects Agency challenged research teams last year to build smaller, more accurate clocks.
Jau is leading one of the two Sandia teams trying to do it.
“They want one cubic centimeter for everything, and currently, there’s no atomic clock with this kind of size,” Jau said in a news release from Sandia.
The core design of the clock Jau and his team are constructing is just 0.04 cubic centimeters, the release said.
DARPA wants these tiny clocks to be accurate within one-millionth of a second after one week.
Sandia has been building compact clocks for decades. It helped develop a 17 cubic centimeter clock, known as the Chip Scale Atomic Clock, in the early 2000s – about the size of a matchbook. It was the smallest atomic clock in the world at the time and is still the smallest one available on the retail market.
The U.S. National Bureau of Standards, now the National Institute of Standards and Technology, invented the first atomic clock in 1948.
These clocks measure time using electromagnetic signals emitted by electrons around an atom, “making it incredibly precise,” according to the release.
Atomic clocks have allowed further innovations to come about, including GPS.
DARPA wants to create small, accurate clocks to help vehicles when GPS is unavailable.
“This works like how you might calculate distance driving a car on a long stretch of highway,” the release said. “If you drive a steady 60 miles per hour, you know after one hour you’ve traveled 60 miles. A trusty clock is half the equation.”
Sandia and DARPA want its clocks to be 30 times more accurate than the current state-of-the-art, small-scale clocks.
They also want improvements in power consumption and sensitivity to both temperature and vibration.
“This is way more challenging than what people have done so far,” Jau said in the release.
Sandia said that shrinking the size, weight, and power of atomic clocks makes it easier for advanced navigation systems to benefit naval vessels, drones, and satellites.
Jau has confidence he and his team can build the clock since the plan is essentially 16 years old, according to the release.
As a physics instructor at Princeton University in 2007, Jau built a prototype he called a laser atomic oscillator.
It performed the same function as an atomic clock but was the size of a toolbox. It had a clocklike pulse stemming from shining a laser through a cloud of potassium atoms.
Plus, it was self-contained. The oscillator did not need outside electronic equipment to control its periodic pulse.
“Support hardware is common in many kinds of atomic clocks, and it usually takes up most of the space,” the release said. “If you removed the support electronics from a matchbook-sized CSAC, you’d find the physical ticking takes place in a package only about the size of a grain of rice.”
Jau built a larger prototype of the atomic clock because doing so is easier.
“You know, with my sausage fingers,” he said in the release.
Jau said he will substitute potassium atoms for cesium and shrink his design by using machines and tools at Sandia’s Microsystems Engineering, Science, and Applications complex. It is a hybrid research, development, and production facility for microelectronics.
Since the design does not need peripheral hardware, Jau thinks he can dramatically shrink the size, weight, and power requirements necessary for atomic clocks.
“We will use only the volume of the physics package that exists in the existing CSAC clock, but we will get rid of those complicated electronics around it,” Jau said in the release.
DARPA provided Jau and his team with two years of funding, and they may receive more if they meet size and performance benchmarks.
