Review of Fe Chalcogenides as the Simplest Fe-Based Superconductor

Abstract

Here we summarize the physical properties of the newly discovered Fe-chalcogenide superconductors. The Fe-chalcogenide superconductors are of great interest because they are the simplest Fe-based superconductors. Furthermore, Fe chalcogenides show a huge pressure effect on their superconducting properties. The origin of the high transition temperature was discussed with change in both the crystal structure and magnetism. Advances in the thin-film and superconducting-wire fabrication are also described.

Electronic structure of FeSe monolayer superconductors

“…A lot of attention was attracted to this system because of its simplicity, though its superconducting characteristics (under normal conditions) were quite modest (T c ∼8K) and its electronic structure was quite similar to that of iron pnictides (cf. review in [7]). …”

Large local disorder in superconducting K0.8Fe1.6Se2studied by extended x-ray absorption fine structure

“…Among these, the FeSe (the 11-type chalcogenide) shows lowest superconducting transition temperature (T c ∼8 K), however, could be considered as a model system to address basic characteristics of these materials [3]. The FeSe structure contains simple stacking of tetrahedrally coordinated FeSe 4 layers without spacer layers that are known to have substantial effect on the electronic properties [4,5].…”

High-TcSuperconductivity near the Anion Height Instability in Fe-Based Superconductors: Analysis ofLaFeAsO1−xOnari1, Yamakawa2, Kontani3 2014Phys. Rev. Lett.70101000View full textAdd to dashboardCite

“…The superconductivity is realized near the structural quantum critical point (QCP) at T S = 0 and/or the magnetic QCP at T N = 0. For example, the optimum T c in FeSe x Te 1−x is realized near the structural QCP at x ≈ 0.6 [1], whereas AFM order is absent for x > 0.5.…”