Superconductors could be extremely useful for future electronics because electricity flows through them without any resistance whatsoever. Superconductivity can make materials highly efficient, but the phenomenon only happens under certain conditions – like ultra-cold temperatures.
University of Tokyo engineers found a new way to create a superconductor out of Bose-Einstein condensate (BEC) – the fifth state of matter. You may know of the three normal states of matter: gas, liquid, and solid. Maybe you even know about a fourth one called plasma, which is essentially a super-hot mess of subatomic particles formed when gas gets so hot all its constituent atoms come apart. Well, there’s yet another state of matter little known about on the complete opposite end of the thermometer. BEC’s are what happens when a gas of bosons is cooled to almost the lowest temperature possible.
Lead author of the study, Associate Professor Kozo Okazaki from the University of Tokyo, said:
A BEC is a unique state of matter as it is not made from particles, but rather waves. As they cool down to near absolute zero, certain materials’ atoms become smeared out over space. This ‘smearing’ increases until the atoms — now more like waves than particles — overlap, becoming indistinguishable from one another. The resulting matter behaves like a single entity with new properties the preceding solid, liquid, or gas states lacked, such as superconduction. Until recently, superconducting BECs were purely theoretical, but we have now demonstrated this in the lab with a novel material based on iron and selenium (a nonmetallic element).
While past experiments with BEC’s have led to creating exotic states of matter – like excitonium, supersolids, fluids exhibiting negative mass, and quantum ball lightning – this new research is the first time a BEC has been verified to work as a superconductor.
The discovery, as it stands, doesn’t have any direct applications for the general public. It only deepens the scientific understanding of the phenomenon, which could help scientists create better superconductors in the future. When better superconductors are created, they could be used to make much faster and more efficient electronics.
Okazaki said:
Demonstrating the superconductivity of BECs was a means to an end; we were really hoping to explore the overlap between BECs and BCSs. It was extremely challenging, but our unique apparatus and observation method have verified it — there is a smooth transition between these regimes. And this hints at a more general underlying theory behind superconduction. It is an exciting time to be working in this field.
With conclusive evidence of superconducting BECs, I think it will prompt other researchers to explore superconduction at higher and higher temperatures. It may sound like science fiction for now, but if superconduction can occur near room temperature, our ability to produce energy would greatly increase, and our energy needs would decrease.
Even though superconducting devices aren’t used in everyday applications yet, some serve higher purposes than just a laboratory curiosity. For example, electromagnets are used in the world’s largest particle accelerator – the Large Hadron Collider. But until someone figures out how to form superconductors at higher temperatures, they’ll only be used in highly specialized equipment.
