Scientists can now confirm – time crystals exist, indeed. They published a study in the journal Physical Review Letter where they described these crystals with atoms which can never reach a state of equilibrium.
Time crystals are actually in a state of thermal equilibrium. What does thermal equilibrium mean? It is actually an example of a new class of matter, which belongs to the nonequilibrium phases. Until now, these phases existed only under the form of theories.
We also know that crystals have patterns that repeat in space. Time crystals are different, because their patterns repeat in time, and not space. Thus, they can never reach equilibrium.
Andrew Potter, an assistant professor of physics at the University of Texas in Austin, said that the researchers took these theories and actually built them in the laboratory. Also, he said that such a discovery might lead to further findings of other nonequilibrium phases.
To create the time crystals, they charged atoms and ions of ytterbium with electricity. Then, by using an electrical field, they raised ten ytterbium ions above a surface in a floating state, and then “hit” them with a laser which made them move and perform flips. They continued hitting the ions until the flips created a pattern that repeated in time.
Potter said that the flips did not repeat as fast as the laser pulses that hit them, which caused them to be in constant motion, but without having any energy. This is precisely the behavior that was expected by the team, which led them to the conclusion that they had created time crystals.
The “recipe” for time crystals was created by Potter and Norman Yao, professor at the University of California Berkeley. They called it a new phase of matter, as it is one of the first examples of matter being in a state of nonequilibrium.
The first who came up with the idea of time crystals was Frank Wilczek from the Massachusetts Institute of Technology, who won the Nobel Prize for physics in 2012. Now, the scientists tested the theory, created the time crystals and confirmed their existence.
Scientists have created the crystals, but they do not know yet what use they might have. They suspect that they might use them in quantum computing for the storage or transfer of information. However, they need to create more crystals and look for other stages of nonequilibrium to see what application they have.
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