MIT scientists just destroyed a quantum record
The record-breaking number could lead to more precise atomic clocks and better GPS signals. The study was published March 26 in the journal Nature.
Quantum entanglement is a bizarre phenomenon where two particles become linked. Anything you do to one particle instantly affects the other no matter how far apart they are - even if one particle is on the Earth and the other is on the moon.
Quantum entanglement is important because scientists can use it to create atomic clocks that are crucial for accurate GPS. The most sophisticated atomic clocks are already really impressive. They're accurate to one second in 300 million years.
That means they "would be less than a minute off if they ran since the Big Bang," Vladan Vuletic, a physics professor at MIT, said in a press release.
This new means of quantum entanglement, however, could make atomic clocks even more accurate. It could also improve GPS navigation since GPS requires clocks with an accuracy to at least one billionth of a second to keep you from getting lost.
The best atomic clocks we have are based on the measurements of spinning atoms. Entangled atoms all spin together and keep a steady beat (just like a pendulum). Atomic clocks send laser light pulses across the field of entangled atoms. The laser measures atom's vibrations to figure out the length of a second. The more entangled atoms there are to measure, the more precise the clock is.
Normally physicists can only entangle pairs of particles or atoms. The previous record was only 100 entangled atoms. This discovery entangled over 3,000. The researchers were able to entangle so many more atoms by using a really weak laser where each laser pulse only contained a single light particle.
Weaker light is better since quantum entanglement is such a fragile state. It only takes a small disturbance to make the whole system collapse. Past experiments have sent thousands or millions of photons through clouds of atoms at once. A pulse with only one light particle is much less likely to disrupt the cloud of entangled atoms.
The researchers say it should be pretty straightforward to entangle even more atoms - even millions. (To put that into perspective, about 500,000 carbon atoms make up the width of a human hair).
This new method could improve the accuracy of atomic clocks by a factor of two. And Vuletic and the team of researchers are already working on a new state-of-the-art atomic clock that could become the new standard of accuracy and lead to better GPS.
The research could also be a step forward in figuring out how to beam encrypted quantum messages around the globe - a much faster way to securely communicate.