Physicists Propose a New Form of Matter Called Superfluid Quasicrystals
In addition to the three fundamental states of matter -- solids, liquids, and gases -- physicists think they've found a new theoretical from of matter: superfluid quasicrystal. Researchers from the University of Texas at Dallas (UT) described the new form in a study published in the journal Physical Review Letters.
And while it might sound like a recipe for a supervillain's masterplan, the researchers detailed a way to make these unique substances in the lab.
There are a number of more states of matter which include plasma and Bose-Einstein condensates -- which exist in the coldest and most extreme temperatures. The new superfluids are unique. The superfluids have zero viscosity and won't lose energy due to friction with a surface. Superfluids like liquid helium can be cooled to extremely low temperatures in order for those properties to emerge. In a statement, the team explained it as an everyday beverage.
“If your morning coffee was a superfluid, and you stirred it with a spoon, you could remove the spoon and the coffee would never stop moving,” said Dr. Chuanwei Zhang, professor of physics in the School of Natural Sciences and Mathematics and corresponding author of the study. “Regular fluids will eventually stop due to friction with the cup.”
The new matter was originally proposed 50 years ago as a supersolid. However, it's only been within the last few years that scientists can produce the material in a laboratory setting.
“In physics, we have a very strict definition of what a fluid is and what a solid is,” Zhang said. “Liquid water cannot behave as a solid, and vice versa. They can be mixed together, for example in a glass of ice water, but they are still separate forms of matter.”
Given the state of quantum physics, however, matter at an atomic level doesn't always function in this way, Zhang noted.
“A supersolid is a fluid flowing without friction whose atoms are also arranged in a periodic way, just as they are in a crystal solid,” he said. “These two states, which are mutually exclusive in our everyday life, can exist at the same time in the same physical material in the quantum world.”
Zhang and his team from UT Dallas suggested that a new type of matter that functions as both a superfluid and a quasicrystal. Unlike traditional crystals, quasicrystals are materials whose atoms are ordered and structured as a crystal but their arrangement doesn't repeat itself.
“We asked the question, can you have a new quantum matter state that is both a quasicrystal and a superfluid?” Zhang said.
The specific material proposed by Zhang et al. would have no friction and also a nonperiodic, quasicrystal structure.
“This is a theory at the moment, but in this paper we suggest an experimental setup similar to the experiment that produced the first supersolids,” Zhang said. “The good news is, we shouldn’t have to invent any new technology to actually make this material. It basically involves shooting lasers at a Bose-Einstein condensate.”
Junpeng Hou serves as lead author of the study and a physics PhD student at UT Dallas. Hou noted that producing the material might still be challenging, even in the most ideal of laboratory settings.
“It can take several years for new supersolids to become experimentally realized,” Hou said. “But I believe our system would not take that long, maybe one or two years.”