Imagine repeatedly tapping a bell with two fingers at uneven rhythms — over time, a haunting pattern emerges. It’s not a simple beat, but something more elusive and eerie. Now imagine doing this not with sound, but with time itself. If your brain feels a bit funny, well, that’s more than understandable.
Yet, in a dazzling experiment, a group of physicists has done just that. They’ve created a new kind of temporal structure called a “discrete time quasicrystal” (DTQC), where the rhythms of quantum spins seem to defy both physics and geometry.
A What?!
A crystal is a material whose atoms or molecules are arranged in a repeating, orderly pattern in space. No matter what type of rock or how fancy it looks, all crystals are basically just ordered arrangements of molecules. The idea of time crystals, however, sounds like something straight out of science fiction.
A time crystal is a phase of matter that breaks time-translation symmetry — it exhibits a repeating pattern in time, even though the system is driven by a steady, periodic force. Unlike a ticking clock, where something moves because it’s being pushed, a time crystal responds by oscillating at a slower rate than the periodic drive itself, creating a stable, self-organized rhythm that doesn’t fade away. This concept is relevant because it reveals that quantum systems can organize not just in space, like regular crystals, but also in time.
“In theory, it should be able to go on forever,” says Chong Zu, assistant professor of physics, one of the study authors. In practice, time crystals are fragile and sensitive to the environment. “We were able to observe hundreds of cycles in our crystals before they broke down, which is impressive.”
Time crystals were a radical idea proposed by Nobel laureate Frank Wilczek just over a decade ago. They have since been demonstrated, but only under special conditions — when systems are kicked at regular intervals, like a kid on a swing pushed at perfect beats.
But what happens if you get a bit wild with your pushing rhythm?
A Different Timing
This is what researchers did in the new study. Instead of a simple, periodic tick-tock, the team behind this new discovery used quasiperiodic driving — two pulsing rhythms based on incommensurate frequencies. That means their ratio isn’t a neat fraction. In this case, the scientists chose the golden ratio (approximately 1.618), a number that keeps popping up in nature.
Using these two frequencies, they zapped a cloud of quantum spins embedded in the diamond. These spins are essentially tiny defects in the crystal called nitrogen-vacancy centers. Thy act like quantum compass needles, and they can be controlled with lasers and microwaves. When they applied their two-frequency pulses, the spins didn’t go haywire. They can be locked into a new kind of rhythm. Not a simple one, but a rhythm nonetheless. The result?
“It’s an entirely new phase of matter,” Zu said.
Groundbreaking physics
The mere existence of time crystals and quasicrystals confirms some of the most ethereal hypotheses in quantum physics, so their existence is inherently useful. Time crystals and now time quasicrystals show that the realm of nonequilibrium quantum matter is far richer than we thought.
This experiment gives us a framework for understanding what can happen when energy is constantly pumped into a system, but instead of going chaotic, the system settles into a strange kind of harmony. It’s a new way of being, and that’s why Zu says it’s a new phase of matter.
What’s more, the robustness of these phases hints at real applications. Because time crystals can theoretically tick forever without losing energy, they could be useful for quantum computers. It’s still early days, but the potential is enormous.
“They could store quantum memory over long periods of time, essentially like a quantum analog of RAM,” Zu said. “We’re a long way from that sort of technology. But creating a time quasicrystal is a crucial first step.”
If you feel confused by this whole thing, well, you’re not alone. Richard Feynman, the brilliant and irreverent physicist, once said, “If you think you understand quantum mechanics, you don’t understand quantum mechanics.” He’d probably say the same about time after reading this study.
Time, in our ordinary experience, is a straight line. It moves forward, evenly, like a metronome. But in the world of quantum spins, time can twist, flip, split, and organize itself into patterns that are neither random nor regular. They’re something else entirely. Something new.
The research has been published in the journal Physical Review X.
