Atomic-scale imaging reveals that chalcogen atoms play a crucial role in Cooper pairing in Fe-based superconductors, offering new insights into high-Tc superconductivity mechanisms. Superconductivity in quantum materials, whether the Cooper pairing on the Fermi surface is mediated by phonons or by electronic fluctuations, is fundamentally described by Bardeen-Cooper-Schrieffer (BCS) theory. In this framework, superconductivity arises […]