In 2016, a group of scientists discovered time crystals, solids with an oscillating internal structure that repeats itself in time, not in space. Now, they found another one, and uniquely found in children's toys.
As reported in two studies published in Physical Review Letters and Physical Review B, researchers have identified typical discrete time crystal (DTC) behavior in mono-ammonium phosphate.
This discovery complicates the theory behind time crystals, as researchers generally believe that these objects require certain 'internal disturbances' to act as time crystals.
The research team grew the crystals for different experiments but wanted to know if they could observe the expected DTC signal in them. They used nuclear magnetic resonance and were surprised to find the signature as fast as they did.
"Our crystal measurements look very striking," said the lead investigator for the two new studies, Professor Sean Barrett, from Yale University, quoted from IFL Science.
"Our work shows that signatures of DTCs can be found, in principle, by looking at persistent crystal growth," he said.
Time crystals are like jelly that can shake strangely. When we shake it, the gelatin oscillates at a frequency that doesn't match our movement. This is what happened with the time crystal. Whatever our initial impulse, the time crystal will assume a certain frequency.
How such a structure could arise is not yet clear. And studies have challenged many of the ideas put forward over the last few years.
"We realized that simply finding a DTC signature doesn't necessarily prove that the system has a quantum memory of how it happened," said Robert Blum, a Yale University graduate student, one of the study's authors.
The team then pushed their investigation further. "This prompted us to experiment with time crystal 'echo', which uncovers hidden coherences, or quantum orders, within systems," said lead author Jared Rovny, also a Yale University graduate student.
Time crystal for what?
Many may ask, what are the real benefits of this research? Time crystals have the potential to improve on established technologies like atomic clocks, magnetometers, even the gyroscopes used in your smartphone to determine their orientation.
Time crystals may even play an important role in emerging quantum technologies, an area of research that is likely to increase in intensity over the next few years.