Physicists have achieved a major breakthrough in the field of quantum physics by developing a time crystal that has a lifespan millions of times longer than previously attained. This discovery confirms the theoretical prediction of time crystals made by Nobel laureate Frank Wilczek in 2012, demonstrating periodic behavior in a system without periodic external influence. Researchers have extended the lifespan of time crystals, validating a theoretical concept proposed by Frank Wilczek. This marks a significant advancement in quantum physics.Researchers at TU Dortmund University have successfully created a highly durable time crystal that lasted millions of times longer than what was previously possible. Their achievement corroborates an extremely interesting phenomenon proposed by Nobel Prize laureate Frank Wilczek around ten years ago, which had already made its way into science fiction movies. The results of their work have been published in Nature Physics.A Significant Breakthrough in Time Crystal ResearchCrystals, or more precisely, crystals in space, are periodic arrangements of atoms over large length scales. This arrangement gives crystals their captivating appearance, with smooth facets like gemstones.Physics frequently treats space and time at the same level, for example in special relativity. In 2012, Frank Wilczek, a physicist at the Massachusetts Institute of Technology (MIT) and a Nobel Prize winner in Physics, suggested that, in addition to crystals in space, there must also be crystals in time. For this to occur, he stated that one of their physical properties would need to begin changing periodically in time spontaneously, even though the system does not experience corresponding periodic interference.The measurement of the new time crystal looks like a flame: Each point corresponds to an experimental value, resulting in different views of the periodic dynamics of the nuclear spin polarization of the time crystal. Credit: Alex Greilich/TU Dortmund UniversityUnderstanding Time CrystalsThere has been heated scientific debate for several years about the possibility of such time crystals, but the concept quickly made its way to the big screen. For instance, a time crystal played a central role in Marvel Studios’ movie Avengers: Endgame (2019). Since 2017, scientists have managed to demonstrate a potential time crystal on a few occasions.Dr. Alex Greilich works at the Condensed Matter research focus of the Department of Physics at TU Dortmund University. Credit: TU Dortmund UniversityHowever, these were systems that – unlike Wilczek’s original idea – are subjected to a temporal excitation with a specific periodicity, but then react with another period twice as long. A crystal that behaves periodically in time, although excitation is time-independent, i.e. constant, was only demonstrated in 2022 in a Bose-Einstein condensate. However, the crystal lasted for just a few milliseconds.A Leap in Time Crystal LongevityThe team of physicists from Dortmund, led by Dr. Alex Greilich, has designed a unique crystal made of indium gallium arsenide, where the nuclear spins act as a reservoir for the time crystal. The crystal is continuously illuminated so that a nuclear spin polarization forms through interaction with electron spins. It is this nuclear spin polarization that spontaneously generates oscillations, similar to a time crystal.The current status of the experiments shows that the crystal has a lifespan of at least 40 minutes, which is ten million times longer than what has been demonstrated previously, and it could potentially endure much longer. The crystal’s period can be modified over wide ranges by systematically altering the experimental conditions. Additionally, it is possible to enter areas where the crystal “melts,” losing its periodicity. These areas are also intriguing as they manifest chaotic behavior, which can persist for long periods of time. This marks the first time scientists have been able to use theoretical tools to analyze the chaotic behavior of such systems.Reference: “Robust continuous time crystal in an electron–nuclear spin system” by A. Greilich, N. E. Kopteva, A. N. Kamenskii, P. S. Sokolov, V. L. Korenev and M. Bayer, 24 January 2024, Nature Physics.
DOI: 10.1038/s41567-023-02351-6