Crystals repeat in their atomic structure through space. But a team of scientists have demonstrated that they can also repeat in time – and in so doing, they have created a whole new form of matter.
Time crystals were created by two separate laboratories, using a blueprint mapped out by a physicist at the University of California – Berkeley, Norman Yao.
The blueprint was published earlier this month in the online journal Physical Review Letters.
“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,” said Yao, in a statement released by the school. “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.”
The time-crystal concept was originally proposed in 2012 by Frank Wilczek, a Nobel laureate and theoretical physicist at MIT.
The structure of these crystals is inherently unable to settle down to motionless stability, like other crystals, from diamonds to snowflakes to quartz.
The time crystals are “kicked” periodically – similar to tapping Jell-O and watching it jiggle, they said.
Teams at the University of Maryland and Harvard University both created their own time crystals, and have submitted papers that are pending publication.
The Maryland team lined up 10 ytterbium ions, then shot them alternately with two lasers: one to create a magnetic field, and the second to flip the atomic spins. Done repeatedly, the atoms settled into a spin-flip pattern which was relatively stable (in their instability).
The Harvard team instead used dense nitrogen nuggets within diamonds to make its time crystal.
Although the time crystals have no pragmatic use currently, the concept of non-equilibrium matter may hold untapped – and unforeseen – uses to humanity in the future, according to a perspective piece by Phil Richerme of Indiana University which accompanied the blueprint paper.
The breakthrough “confirms that symmetry breaking can occur in essentially all natural realms,” the experimental atomic physicist writes.
“Such similar results achieved in two wildly disparate systems underscore that time crystals are a broad new phase of matter, not simply a curiosity relegated to small or narrowly specific systems,” Richerme adds.