Depth-resolved magnetic order in superconducting topological insulator/FeTe thin film heterostructures

Despite being structurally and chemically similar to the prominent superconductor FeSe, FeTe is antiferromagnetic and non-superconducting in the bulk. While it has often been presumed that the magnetism and lack of superconductivity in this material are linked, findings relating the two yield conflicting results and are complicated by phase separation. Using a range of topologically nontrivial capping layers to stabilize interfacial FeTe superconductivity, the authors show that the suppression of the antiferromagnetic state in FeTe is unlikely to be the primary factor driving superconductivity. Instead, They find evidence that subtle changes in Fe content likely drive the transition.