Aboard the International Space Station is a compact laboratory the size of a small refrigerator that produces some of the coldest things in the universe. It’s called the Cold Atom Lab, and for some time now, scientists have been using this chamber to research the strange quantum properties of atoms in microgravity. But on Wednesday (November 15), they announced they had reached a milestone.
Operated remotely by a team at NASA’s Jet Propulsion Laboratory (JPL) in California, the Cold Atom Lab has officially generated a quantum gas containing two species of atoms. Ultimately, this could open the door to entirely new space experiments in quantum chemistry.
Matter can exist in five known states. Gases, liquids, solids and plasmas are the best known – but there is also an exotic fifth state of matter, the Bose-Einstein condensatewhich was first discovered in the 1990s.
This state of matter has not been found in nature, but scientists can create it. Bose-Einstein condensates are generated in ultracold laboratories like the Cold Atom Lab, where lasers or magnets help cool a cloud of atoms close to absolute zero, or -459 degrees Fahrenheit (-273 degrees Celsius). This is the coldest possible temperature in the universe. In this state, atoms slow down, their edges blend together, and scientists can observe quantum effects that are usually very difficult to investigate.
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On Earth, gravity causes Bose-Einstein condensates to dissipate when supercooling magnets or lasers in the experimental chamber are turned off. This, however, would not happen in the microgravity environment of space. As such, scientists created Bose-Einstein condensates in the Cold Atom Lab for the first time in 2018, the year the camera was installed on the ISS. And in years sincethey studied the phenomenon to great effect.
But now, researchers have demonstrated that they can create this quantum gas with not just one, but two types of atoms. In this case, they achieved the feat with a potassium-rubidium cloud. According to a JPL announcementFuture work with this type of quantum gas could be used to help develop space-based quantum technologies that already exist on Earth.
“We could make sensors extremely sensitive to small rotations and essentially use these cold atoms in Bose-Einstein condensate to make gyroscopes,” said Nicholas Bigelow, professor of physics and optics at the University of Rochester, in a statement. declaration. He is a co-author of the new findings.
“These gyroscopes could provide us with a fixed reference point in space that could be used for deep space navigation,” Bigelow said. “We are also developing a number of things that could lead to better clocks in space, which are crucial for many things in modern life, such as high-speed internet and GPS.”
The researchers also think that future experiments at the Cold Atom Lab could help them test the equivalence principle, central to Albert Einstein’s theory of general relativity. This principle states that gravity should affect all objects in the same way, regardless of their masses. In other words, a feather and a brick should fall at the same rate – at least in a vacuum, where there is no friction.
Scientists have had difficulty resolving this principle with the laws of quantum mechanics, which describe how the smallest known objects in the universe behave. They will be able to test it more precisely in quantum experiments in space.
A paper detailing these findings was published November 15 in the journal Nature.