Visualizing the intricate electron pairing in iron-based superconductors
Correlated motion provides new clues to the magnetic origin of high-temperature superconductivity
Superconducting wires conduct electricity perfectly — without any energy losses — because each electron spontaneously bonds to a partner electron. The pairs then perform an intricate dance down the wire, never bumping into the walls or other pairs. Unfortunately, the pairs are usually weak, breaking apart at all but the coldest temperatures, destroying the superconductivity and limiting most practical applications. Scientists are pursuing the possibility of electron pairing in a special class of materials (nearly antiferromagnetic compounds) hoping to find magnetically mediated superconductivity at ever higher temperatures.
For the first time, researchers at Cornell University have directly imaged the intricate dance of electron pairs in a new type of iron-based superconductor using a highly specialized scanning tunneling microscope. As predicted by theories of magnetically mediated electron pairing, the strength of electron-electron bonding is different for electrons travelling in different directions. The electronic structure images provide new clues to the magnetic origin of high-temperature superconductivity, bringing practical superconductors a step closer to reality.