They sound like something straight of science fiction – and in a way they are. They are not totally understood… Their existence was only suggested in 2012.Only recently have researchers (from Maryland/Havard University) managed to make them, as you can read here.
First of all, a crystal is just something made of a repeating structure – such as an emerald or a block of ice. They are called time crystals because they exist in a fourth dimension:time.
They are extremely weird. Without energy – matter was thought to reach a ‘ground state’ where no movement can take place, because that would require energy. Time crystals appear to flip in and out of this ‘ground state’. This is not a perpetual motion machine though because total energy remains the same.
Norman Yao describes the oscillations by saying ‘It’s like playing with a jump rope, and somehow our arm goes around twice, but the rope only goes around once,’ The atoms will oscillate at a different rate to the frequency of light pulsed in.
Why is this so important?
Creating stable quantum states can be very useful in quantum computing. These crystals can help to protect these developing computers because they are very sensitive to outside interference.