skip to main content

DOE PAGESDOE PAGES

Title: The role of double TiO 2 layers at the interface of FeSe/SrTiO 3 superconductors

We determine the surface reconstruction of SrTiO 3 used to achieve superconducting FeSe films in experiments, which is different from the 1×1 TiO 2-terminated SrTiO 3 assumed by most previous theoretical studies. In particular, we identify the existence of a double TiO 2 layer at the FeSe/SrTiO 3 interface that plays two important roles. First, it facilitates the epitaxial growth of FeSe. Second, ab initio calculations reveal a strong tendency for electrons to transfer from an oxygen deficient SrTiO 3 surface to FeSe when the double TiO 2 layer is present. The double layer helps to remove the hole pocket in the FeSe at the Γ point of the Brillouin zone and leads to a band structure characteristic of superconducting samples. The characterization of the interface structure presented here is a key step towards the resolution of many open questions about this superconductor.
Authors:
 [1] ;  [2] ;  [1] ;  [1] ;  [3] ;  [1] ;  [1] ;  [1] ;  [2] ;  [1] ;  [1] ;  [3] ;  [1] ;  [1] ;  [1]
  1. Yale Univ., New Haven, CT (United States)
  2. Yale Univ., New Haven, CT (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)
  3. Fudan Univ., Shanghai (China)
Publication Date:
Report Number(s):
BNL-112212-2016-JA
Journal ID: ISSN 2469-9950; PRBMDO; R&D Project: MA509MACA; KC0203020; TRN: US1601742
Grant/Contract Number:
SC0012704
Type:
Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 93; Journal Issue: 18; Journal ID: ISSN 2469-9950
Publisher:
American Physical Society (APS)
Research Org:
Brookhaven National Laboratory (BNL), Upton, NY (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
OSTI Identifier:
1255726
Alternate Identifier(s):
OSTI ID: 1253228