Microscopic origin of superconductivity in FeTe-based heterostructures

Determine the microscopic origin of superconductivity in FeTe-based heterostructures, including the roles of interfacial chemical composition, strain, charge transfer, spin texture, and interfacial phonons.

Background

FeTe-based heterostructures exhibit interfacial superconductivity despite the absence of superconductivity in conventional bulk FeTe containing interstitial iron. The heterostructures also combine superconductivity with magnetic and topological overlayers, making them candidates for studying the interplay of superconductivity, magnetism, and topology.

Several mechanisms have been proposed for the emergence of superconductivity, including changes in chemical composition, strain, charge transfer, spin texture, and interfacial phonons. Although the paper establishes a whole-sample Meissner response and argues that the interfacial FeTe layer is the common superconducting component, it does not uniquely determine the microscopic mechanism responsible for superconductivity.