Researchers Create Coldest Molecules On Earth That Are Colder than Interstellar Space

Researchers at MIT have managed to create the coldest stable molecules in the world that are over a million times colder than interstellar space. They made it possible by cooling molecules in a gas of sodium potassium (NaK) to a temperature of 500 nanokelvins, which is just a hair above absolute zero.

The newly developed molecules are still, contrary to common behavior of molecules, i.e., full of energy, vibrating and rotating through space.

"We are very close to the temperature at which quantum mechanics play a big role in the motion of molecules," said Martin Zwierlein, one of the researchers, in a news release. "So these molecules would no longer run around like billiard balls, but move as quantum mechanical matter waves. And with ultracold molecules, you can get a huge variety of different states of matter, like superfluid crystals, which are crystalline, yet feel no friction, which is totally bizarre. This has not been observed so far, but predicted. We might not be far from seeing these effects, so we're all excited."

Each molecule is composed of individual atoms that are bonded together to form a molecular structure, such as the sodium potassium molecules used in this study.

Researchers used lasers and evaporative cooling to cool clouds of individual sodium and potassium atoms to near absolute zero.

The achievement could reveal the wacky physics that occur at jaw-dropping cold temperatures.

Findings of the study have been published in the journal Physical Review Letters.