Discovery of “Pseudogap” Behavior in a Monolayer Thick High-Temperature Superconductor

The ability to produce pristine atomic interfaces by growing the structures atom-by-atom :via: molecular beam epitaxy has opened the door to an entirely new class of emergent phenomena in the form of interface quantum materials. One remarkable example of such a material system is the interface between monolayer iron selenide (FeSe) films and SrTiO:3:, where superconductivity can be observed at dramatically higher temperatures compared to 8 K of bulk FeSe. So far, the inherent fragility of such ultra-thin layers has prevented the direct study of superconductivity :via: direct probes like electrical resistivity.