High-temperature superconductor 'fingerprint' found

Theorists and experimentalists working together at Cornell may have found the answer to a major challenge in condensed matter physics: identifying the smoking gun of why "unconventional" superconductivity occurs, they report , published online Dec. 22.

Associate professor of physics Eun-Ah Kim led the way, joining forces with experimentalist J.C. Seamus Davis, the J.G. White Distinguished Professor of Physical Sciences in the College of Arts and Sciences. They have isolated a "fingerprint" that identifies specific fluctuations in electrons that force them into pairs, causing their host material, in this case, a high-temperature superconductor called lithium iron arsenic, to make way for free-flowing, resistance-free electron pairs.