This latest discovery shows how you can never rule out even the craziest of things when it comes to science! Researchers have confirmed a brand new phase of matter, time crystals, which look to change our basic understanding of material sciences!
These strange crystals have an atomic structure that repeats in the time domain rather than space. Thus the atoms are in constant oscillation without requiring external energy. A physical object which exists without energy is added to the fourth dimension “movement of time,” which is exactly what makes the time crystals so unique.
Time crystals are series of atoms arranged in a circle. These atoms in the crystals are held by the magnetic field, and the temperature is kept cold so that nothing interferes with them. All the atoms in the time crystals carry a negative charge.
Usually when a material exists in its ground state, also called the zero-point energy of a system, the movement of the atoms is theoretically impossible since it would require it to expend energy which it lacks.
Normal crystals’ atomic structure repeat in space, known as an atomic lattice, just like the carbon lattice of a diamond. But they are motionless when in equilibrium in their ground state. Time crystals are different as they a structure that repeats in time, not in space, and the atoms keep oscillating even in its ground state without needing any energy.
This could be thought of as like jelly; when it is tapped, it repeatedly jiggles. The same thing phenomenon happens in time crystals, the difference being that the motion occurs without any external energy requirements. This is what makes time crystals a whole new phase of matter known as the non-equilibrium matter which is incapable of sitting still.
The material exists in its ground state and also appears to violate fundamental physics law “time translation symmetry” i.e. it has an asymmetrical ground state. So, from wherever you will look at the crystal, it will appear different.
Researchers from the University of California purposed a concept in Physical Review Letters that how time crystals don’t break symmetry explicitly but rather spontaneously. If symmetry is broken explicitly, then the laws of nature will not have symmetry anymore.
What wonders the physicists the most is that time crystals are in the non-equilibrium state, which was first predicted by Nobel-Prize winning theoretical physicist Frank Wilczek in 2012.
Researcher Norman Yao from the University of California, Berkeley was the lead behind the discovery. He talked about the astonishing feat:
“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 Physics Review Letters, it is mentioned that Yao and his team describes how to predict and measure the properties of time crystals and also the fact that what phases are required to keep the time crystals in, just like the liquid and gas phases of ice.
Based on Yao and his team’s explanation, University of Maryland and Harvard University came up with their first-time crystal but made by using totally different methods and posted their publications online on arXiv.org and in peer review journals.
At the University of Maryland, time crystal was created by Chris Monroe and his colleagues using a conga line of 10 ytterbium ions, entangled with electronic spins. To bring the ions from their natural equilibrium state to non-equilibrium state, the researchers hit the ion with the first laser to create a magnetic field and then hit it with the second laser to partially flip the spins. Because the spins interacted, the atoms settle into a stable and repetitive pattern of spin flipping which defines a crystal. The two lasers served to produce a pattern in the ions i.e. create a repetition in the system with twice the period of the drivers.
At Harvard University, the researchers created the same time crystals but with an totally different experiment. They used densely packed nitrogen vacancy in diamonds to conduct the experiment.
In Physics Review Letters, Phil Richerme of Indiana University said:
“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”
According to MIT review reports, now the process of making time crystals is fairly simple. A quantum system is needed, on which a bunch of ions is held in a shape of a ring and cooled them to their lowest energy state. If the system breaks symmetry, then the ring would rotate periodically in time, breaking the law of “time translation symmetry.” Obviously, it would never be obvious to extract energy from this motion, because then it would violate the concept of conservation of energy.
While even Yao has not been fully able to describe the use of the time crystals clearly, it has been predicted that it may be useful in quantum computers and it may be used to send the information back and forward in time.
Learn more about time crystals in the video below!
Source: Physical Review Letters