New Tweezer clock tells time more precisely

Newer atomic clocks that measure optical frequencies of light are even more precise, and may eventually replace the radio-based ones.


Scientists at the Caltech and the Jet Propulsion Laboratory (JPL) have developed a new design for an optical atomic clock that holds promise to be the most accurate and precise yet. Dubbed as ‘tweezer clock,’ it is based on an array of individually trapped neutral atoms with single-atom readout, merging many of the benefits of ion and lattice clocks as well as creating a bridge to recently developed techniques in quantum simulation and computing with neutral atoms.

Manuel Endres, an assistant professor of physics at Caltech, said, “One of the goals of physicists is to be able to tell time as precisely as possible. While the ultra-precise clocks may not be needed for everyday purposes of counting time, they could lead to advances in fundamental physics research as well as new technologies that are yet to be imagined.”

As mentioned above, this new clock is built upon two types of optical atomic clocks: 1. A single trapped charged atom, or ion, 2. An optical lattice composed of thousands of neutral atoms trapped in.

In the trapped-ion approach, just a single atom (the ion) should be isolated and controlled, and this improves the precision of the clock. Then again, the optical lattice approach profits by having numerous atoms—with more atoms, there are fewer vulnerabilities that emerge because of random quantum fluctuations of individual atoms.

Its design essentially composed of the advantages of the two designs, reaping the benefits of both. Instead of using a collection of many atoms, the design consisting of 40 atoms, and those atoms are precisely controlled with laser tweezers.

This way, this design benefits not only from having multiple atoms but also by allowing researchers to control those atoms.

Ivaylo Madjarov, a Caltech graduate student and lead author of the new study, said, “This approach bridges two branches of physics—single-atom control techniques and precision measurement. We’re pioneering a new platform for atomic clocks.”

“In general, the atoms in atomic clocks act like tuning forks to help stabilize the electromagnetic frequencies of laser light. The oscillations of our laser light act as a pendulum that counts the passage of time. The atoms are a very reliable reference that makes sure that pendulum swings at a constant rate.”

The team says that the new system is ideally suited for future research into quantum technologies. The atoms in these systems can become entangled, or globally-connected, and this entangled state can further stabilize the clock.

Endres said, “Our approach can also build a bridge to quantum computation and communication architectures. By merging different techniques in physics, we’ve entered a new frontier.”

The paper is published in the journal Physical Review X.