Proving that there is still so much for science to discover, two groups of scientists have created a new phase of matter called time crystals. Based on a blueprint from University of California, Berkeley assistant professor of physics Norman Yao, the scientists created crystals whose structure repeats in time rather than space. If time crystals sound like a far-fetched science fiction daydream, Yao explained they move somewhat like jiggling Jell-O, but through time.
Regular crystals, like diamonds, are comprised of an atomic lattice, an arrangement of atoms, that repeats in space. Time crystals’ structure can continue through time, in perpetual movement. Yao said, “Wouldn’t it be super weird if you jiggled the Jell-O and found that somehow it responded at a different period? But that is the essence of the time crystal.”
The creation of time crystals in itself is crazy, but Yao said that’s not the only thrilling aspect of this advance. In a statement, he said, “This is a new phase of matter, period, but it is also really cool because it is one of the first examples of non-equilibrium matter. For the last half-century, we have been exploring equilibrium matter, like metals and insulators. We are just now starting to explore a whole new landscape of non-equilibrium matter.” In contrast, other crystals like rubies or diamonds are in motionless equilibrium, but as non-equilibrium matter time crystals continually move.
Groups at Harvard University and the University of Maryland followed Yao’s blueprint and were able to create time crystals, turning futuristic fantasy into reality. They used “two totally different setups,” according to the UC Berkeley statement, and have both submitted articles for publication, with Yao as co-author on both. Physical Review Letters published a paper online earlier this month in which Yao detailed the process to create time crystals.
There may be few uses for time crystals – Yao couldn’t immediately think of any – but their discovery is important as scientists begin exploring non-equilibrium matter, other phases of which could be useful, for example, in quantum computers.