Tuning the band structure and superconductivity in single-layer FeSe by interface engineering
Open Access
- 26 September 2014
- journal article
- research article
- Published by Springer Science and Business Media LLC in Nature Communications
- Vol. 5 (1), 5044
- https://doi.org/10.1038/ncomms6044
Abstract
The interface between transition metal compounds provides a rich playground for emergent phenomena. Recently, significantly enhanced superconductivity has been reported for single-layer FeSe on Nb-doped SrTiO3 substrate. Yet it remains mysterious how the interface affects the superconductivity. Here we use in situ angle-resolved photoemission spectroscopy to investigate various FeSe-based heterostructures grown by molecular beam epitaxy, and uncover that electronic correlations and superconducting gap-closing temperature (Tg) are tuned by interfacial effects. Tg up to 75 K is observed in extremely tensile-strained single-layer FeSe on Nb-doped BaTiO3, which sets a record high pairing temperature for both Fe-based superconductor and monolayer-thick films, providing a promising prospect on realizing more cost-effective superconducting device. Moreover, our results exclude the direct correlation between superconductivity and tensile strain or the energy of an interfacial phonon mode, and highlight the critical and non-trivial role of FeSe/oxide interface on the high Tg, which provides new clues for understanding its origin.This publication has 28 references indexed in Scilit:
- Measurement of an Enhanced Superconducting Phase and a Pronounced Anisotropy of the Energy Gap of a Strained FeSe Single Layer inHeterostructures Using Photoemission SpectroscopyPhysical Review Letters, 2014
- Interfacial effects on the spin density wave in FeSe/SrTiOthin filmsPhysical Review B, 2014
- Direct Observation of High-Temperature Superconductivity in One-Unit-Cell FeSe FilmsChinese Physics Letters, 2014
- Atomic and electronic structures of single-layer FeSe on SrTiO(001): The role of oxygen deficiencyPhysical Review B, 2013
- Interface-induced superconductivity and strain-dependent spin density waves in FeSe/SrTiO3 thin filmsNature Materials, 2013
- Phase diagram and electronic indication of high-temperature superconductivity at 65 K in single-layer FeSe filmsNature Materials, 2013
- High-temperature superconductivity at the FeSe/SrTiOinterfacePhysical Review B, 2012
- Interface-Induced High-Temperature Superconductivity in Single Unit-Cell FeSe Films on SrTiO 3Chinese Physics Letters, 2012
- Electronic origin of high-temperature superconductivity in single-layer FeSe superconductorNature Communications, 2012
- High-Temperature Superconductivity in a Single Copper-Oxygen PlaneScience, 2009