National Institute of Standards and Technology (NIST) researchers have accomplished another remarkable first in the world of timekeeping. Their aluminum ion clock has set a world record of an astonishing 19 decimal places of accuracy! A focused team, including Mason C. Marshall, first author of the paper, created this groundbreaking technology. That’s because it raises scientific measurements to an entirely new level of detail.
The clock’s precision just got a major upgrade with a new vacuum chamber. These advanced techniques have brought down systematic uncertainty to an all-time low of 5.5×10−19. This jump in precision creates unparalleled opportunities for scientific discovery. It might even result in a redefinition of the second and drive discoveries of new physics.
Redesigning Precision
The NIST’s team set out to accomplish an extremely ambitious project. This necessitated a significant redesign of the vacuum chamber, into which they trap their aluminum ions. Through the use of titanium, however, they were able to eliminate background hydrogen gas by a staggering 150 times. This key change allowed the clock to run without interruptions. Now, because it no longer needs to reload the ion trap every 30 minutes, its operational duration has increased to several days.
The redesign extends the clock’s operational time, but its impact on the stability and accuracy of the clock is even more pronounced. The probing time for the ions has increased by three orders of magnitude. It has increased from a cap of 150 milliseconds all the way up to one second. Thanks to improvements in cooling, researchers can now take measurements with repeatability to the 19th decimal place within a day and a half. That’s a huge change from the prior notice of three weeks!
“It’s exciting to work on the most accurate clock ever.”
At the core of the aluminum ion clock is an atomic physics technique called quantum logic spectroscopy. This cutting-edge approach employs a “buddy system” for ions to make its measurements more accurate. This method provides for enriched associations between the emitter ions offering increased signal detection and richer measurement robustness. One of our graduate students who is currently developing this new measurement approach, Willa Arthur-Dworschack, expanded on this promising new avenue, stating,
Innovative Techniques in Timekeeping
The fresh interdisciplinary collaboration between experienced veteran researchers andrew student research assistants has proven valueadd in achieving this significant breakthrough. The team’s work serves as a perfect example of how collaborations with academia can lead to significant breakthroughs in technology.
“This ‘buddy system’ for ions is called quantum logic spectroscopy.”
The clock’s design and operational improvements have made it 41% more accurate than its predecessor, Ye’s strontium lattice clock, while boasting a stability that is 2.6 times greater than any other ion clock in existence.
The implications of this precision are vast. The aluminum ion clock in particular has the promise to propel transformative scientific breakthroughs. It would enormously advance precision measurements of the Earth’s geodesy and study phenomena beyond the Standard Model of physics. The potential to vary fundamental constants of nature is one of the most exciting avenues to explore with this new-found precision.
Implications for Science and Technology
Marshall emphasized the long-term vision that drives their research efforts at NIST:
This victory marks close to 20 years of dogged advancement in aluminum ion clock know-how. It’s a powerful illustration of how sustained, curious research can lead to profound breakthroughs in precision measurement.
“At NIST we get to carry out these long-term plans in precision measurement that can push the field of physics and our understanding of the world around us.”
Researchers are looking ahead to more development. Looking ahead, they intend to push the frontier of clock architectures, scaling the number of clock ions up and studying entanglement to enhance measurement precision. Arthur-Dworschack noted this potential for future innovations:
Further advancements are on the horizon as researchers look to explore more complex clock architectures by potentially scaling up the number of clock ions and investigating entanglement to enhance measurement capabilities. Arthur-Dworschack noted this potential for future innovations:
“With this platform, we’re poised to explore new clock architectures—like scaling up the number of clock ions and even entangling them—further improving our measurement capabilities.”