Physicists Use Fifth State of Matter to Create Superconductivity
Superconductors are materials that allow electricity to flow without any resistance, and could prove to be hugely beneficial for the future of electronics.
The team's research was published in Science Advances on Friday.
The well-known states of matter are liquids, solids, and gases, then come plasmas. The lesser-known of them all are BECs, which happen when you cool a gas of bosons down to the coldest temperature possible.
At that point, researchers have shown that quantum phenomena can be noticed at macro scales. "A BEC is a unique state of matter as it is not made from particles, but rather waves," said Kozo Okazaki, lead author of the study. "As they cool down to near absolute zero, the atoms of certain materials become smeared out over space."
"The resulting matter behaves like it’s one single entity with new properties the preceding solid, liquid or gas states lacked," Okazaki continued.
Creating superconductivity in a BEC
Now, the team has demonstrated that it's possible to create superconductivity in a BEC—something that has never been confirmed in other experiments.
The team managed this by making a BEC out of a cloud of iron and selenium atoms. And the main part of the discovery happened thanks to an overlap with a similar form of matter known as a Bardeen-Cooper-Schrieffer (BCS) regime.
The team looked at what would happen during the transition between a BCS and a BEC, and whether or not superconductivity was possible in BECs. So far, it had only been possible in BCSs.
Sure enough, superconductivity could also be observed in BECs.
"It was extremely challenging but our unique apparatus and method of observation has verified it – there is a smooth transition between these regimes. And this hints at a more general underlying theory behind superconduction," explained Okazaki.