Ubiquitous strong electron-phonon coupling at the interface of FeSe/SrTiO<sub>3</sub>.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 28186084.
- Also identified by DOI 10.1038/ncomms14468 and PMC identifier 5311057.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The observation of replica bands in single-unit-cell FeSe on SrTiO<sub>3</sub> (STO)(001) by angle-resolved photoemission spectroscopy (ARPES) has led to the conjecture that the coupling between FeSe electrons and the STO phonons are responsible for the enhancement of T<sub>c</sub> over other FeSe-based superconductors. However the recent observation of a similar superconducting gap in single-unit-cell FeSe/STO(110) raised the question of whether a similar mechanism applies. Here we report the ARPES study of the electronic structure of FeSe/STO(110). Similar to the results in FeSe/STO(001), clear replica bands are observed. We also present a comparative study of STO(001) and STO(110) bare surfaces, and observe similar replica bands separated by approximately the same energy, indicating this coupling is a generic feature of the STO surfaces and interfaces. Our findings suggest that the large superconducting gaps observed in FeSe films grown on different STO surface terminations are likely enhanced by a common mechanism.