# MIT creates a new type of atomic clock with even more precision

Researchers at MIT have created a new type of atomic clock that keeps time with more precision than current models. Their new design relies on entangled atoms and could help scientists detect dark matter and study gravity's effects on time. Atomic clocks have been around for a long time and are the most precise timepieces in the world.

Atomic clocks use lasers to measure the vibrations of atoms, which oscillate at a constant frequency. The best atomic clocks in the world can keep time so precisely that had they began operation at the beginning of the universe, that would only be off by half a second today. As precise as current atomic clocks are, MIT's new model is even more precise. Researchers say that more precise clocks are key to answering some incredible questions, such as the impact of gravity on time and if time changes as the universe ages.

The new atomic clock measures atoms that have been quantum entangled. The atoms are correlated in a way that's not possible according to the laws of classical physics and allows the scientists to measure how they vibrate more accurately. The new clock can achieve the same precision but is four times faster than clocks without entanglement.

MIT researcher and lead author of the study Edwin Pedrozo-Penafiel said that entanglement-enhanced optical atomic clocks have the potential to reach better precision in a second than current state-of-the-art optical clocks. The researcher says that if current state-of-the-art atomic clocks were adapted to measure entangled atoms, the timing would improve so that over the entire age of the universe, the clocks would be off by less than 100 milliseconds.

Today's atomic clocks are designed to measure gas composed of thousands of the same type of atoms to get an estimate of average oscillations. Typical atomic clocks use a system of lasers to capture a gas of ultracold atoms in a trap formed by the laser. Another highly stable laser with a frequency close to that of the atoms probes the atomic oscillation and keeps track of time. The researchers were funded in part by DARPA, the National Science Foundation, and the Office of Naval Research.