Observation of topological superconductivity on the surface of an iron-based superconductor
By Peng Zhang, K. Yaji, T. Hashimoto, Y. Ota, T. Kondo, K. Okazaki, Zhijun Wang, J. Wen, G. Gu, H. Ding and 1 more. Science, 2017
684 citations recorded by the source corpus.
A topological superconductor A promising path toward topological quantum computing involves exotic quasiparticles called the Majorana bound states (MBSs). MBSs have been observed in heterostructures that require careful nanofabrication, but the complexity of such systems makes further progress tricky. Zhang et al. identified a topological superconductor in which MBSs may be observed in a simpler way by looking into the cores of vortices induced by an external magnetic field. Using angle-resolved photoemission, the researchers found that the surface of the iron superconductor FeTe0.55Se0.45 satisfies the required conditions for topological superconductivity. Science, this issue p. 182 Angle-resolved photoemission spectroscopy indicates that FeTe0.55Se0.45 harbors Dirac-cone–type spin-helical surface states. Topological superconductors are predicted to host exotic Majorana states that obey non-Abelian statistics and can be used to implement a topological quantum computer. Most of the proposed topological superconductors are realized in difficult-to-fabricate heterostructures at very low temperatures. By using high-resolution spin-resolved and angle-resolved photoelectron spectroscopy, we find that the iron-based superconductor FeTe1–xSex (x = 0.45; superconducting transition temperature Tc = 14.5 kelvin) hosts Dirac-cone–type spin-helical surface states at the Fermi level; the surface states exhibit an s-wave superconducting gap below Tc. Our study shows that the surface states of FeTe0.55Se0.45 are topologically superconducting, providing a simple and possibly high-temperature platform for realizing Majorana states.
Subfields: Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Materials Chemistry
View Paper: https://www.semanticscholar.org/paper/b107d011b7b1e6b02b3fd61fad5b4055e48a59b0
Citations in the corpus
- Angle-resolved photoemission studies of quantum materials (2020, neutral): “These states are spin-polarized, and exhibit an isotropic superconducting gap up to 1.8 meV with Tc=14.5 K (Zhang et al., 2018).”
- Flat bands, strange metals and the Kondo effect (2023, neutral): “Kondo lattice behaviour arises most typically in rare-earth (or actinide)-based intermetallics, which contain both localized 4 f (or 5 f ) electrons and itinerant s -derived, p -derived and d -derived electrons (Fig.”