Resonant Inelastic X-Ray Scattering (RIXS) experiments on the iron-based ladder BaFe2Se3unveiled an unexpected two-peak structure associated with local orbital (
Fe-based superconductors exhibit a diverse interplay between charge, orbital, and magnetic ordering. Variations in atomic geometry affect electron hopping between Fe atoms and the Fermi surface topology, influencing magnetic frustration and the pairing strength through changes of orbital overlap and occupancies. Here, we experimentally demonstrate a systematic approach to realize superconductivity without chemical doping in BaFe2As2, employing geometric design within an epitaxial heterostructure. We control both tetragonality and orthorhombicity in BaFe2As2through superlattice engineering, which we experimentally find to induce superconductivity when the As−Fe−As bond angle approaches that in a regular tetrahedron. This approach to superlattice design could lead to insights into low-dimensional superconductivity in Fe-based superconductors.
more » « less- NSF-PAR ID:
- 10184677
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 117
- Issue:
- 35
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- p. 21170-21174
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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