Two Korean physicists and their research team observed an exotic atomic state called "time crystal." The theoretical concept has been realized through experiments for the first time in the world five years after it was suggested.
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Choi Joon-hee |
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Choi Soon-won |
Choi Joon-hee and Choi Soon-won, Korean graduate students at Harvard University, have worked with researchers including Mikhail Lukin and Renate Landig to theorize and experiment with the time crystal. Their achievement was published in the international scientific journal Nature in its Thursday edition.
The observation of time crystals is expected to expedite research in diverse physical sciences such as quantum computing, according to the researchers.
"This is an observation of a material state that hasn't been revealed so far," Choi Joon-hee said.
The concept of a time crystal was first released as a theoretical idea by Nobel laureate and Massachusetts Institute of Technology professor Frank Wilczek in 2012. Time crystals are an exotic, non-equilibrium state of matter in which the same structures repeat themselves in time whereas ordinary crystals get their periodicity from the regular repetition of spatial elements, according to Nature. Time crystals extend the three-dimensional symmetry seen in ordinary crystals as they spontaneously break the symmetry of time translation.
The Harvard team used diamonds and a million randomly-distributed nitrogen-vacancies to demonstrate time crystal's regularity on a massive scale. The demonstration showed that time crystals can easily occur in nature.
"The experiment by the Harvard research team is quite different from the existing suggestions of experimental methods. The observation will provide a source for more new theoretical studies," Choi Soon-won said. "Research on time crystal's nature is still in an early stage and it is expected to lead to more diverse interesting subjects."
Choi Soon-won graduated from Daejeon Science High School in Korea and the California Institute of Technology before continuing his studies for a doctoral degree at the department of physics at Harvard. Choi Joon-hee studied at Hansung Science High School and the Korea Advanced Institute of Science and Technology. He is currently in the doctoral program of applied physics at Harvard.
Besides the Harvard team, another group of researchers at the University of Maryland, including professors Christopher Monroe and Zhang Jiehang, separately conducted experiments. Unlike the Harvard team, the University of Maryland team used Ytterbium ions trapped and aligned by an electromagnetic field for the experiment.
The Maryland team's research was also introduced in Nature's Thursday edition.