Scientists have manufactured a new form of matter. Findings published online this week by the journal Physical Review Letters describe the so-called fermionic condensate, which is composed of pairs of atoms in a gas at temperatures close to absolute zero. Its creators hope it will inform the design of room-temperature superconductors in the future.
The 1995 production of a Bose-Einstein condensate, in which thousands of ultracold atoms occupy the same quantum state and therefore behave identically, garnered a Nobel Prize in Physics. Ever since, scientists around the world have been working on an appropriate follow-up, says Eric Cornell of the National Institute of Standards and Technology (NIST) and the University of Colorado at Boulder, one of the three recipients of the prize. Now Deborah S. Jin and her colleagues (also at NIST and UC-Boulder) have succeeded. By cooling potassium atoms inside a vacuum chamber to 50 nanokelvin and applying magnetic fields and laser light, the researchers induced the atoms--which typically resist occupying the same quantum state as any of their neighbors--to pair up. Once paired, the atoms¿ aversion to acting alike lessened, allowing the team to observe condensation. (The spike in the image above represents the fermionic condensate.)
The coupling is similar to that seen in superconductors, when electrons become paired and move through the material with no resistance. "The strength of pairing in our fermionic condensate, adjusted for mass and density, would correspond to a room-temperature superconductor," Jin notes. "This makes me optimistic that the fundamental physics we learn through fermionic condensates will eventually help others design more practical superconducting materials."