@article{70472c4fa8794f038f835b94f6e62910,
title = "Control of Epitaxial BaFe2As2 Atomic Configurations with Substrate Surface Terminations",
abstract = "Atomic layer controlled growth of epitaxial thin films of unconventional superconductors opens the opportunity to discover novel high temperature superconductors. For instance, the interfacial atomic configurations may play an important role in superconducting behavior of monolayer FeSe on SrTiO3 and other Fe-based superconducting thin films. Here, we demonstrate a selective control of the atomic configurations in Co-doped BaFe2As2 epitaxial thin films and its strong influence on superconducting transition temperatures by manipulating surface termination of (001) SrTiO3 substrates. In a combination of first-principles calculations and high-resolution scanning transmission electron microscopy imaging, we show that Co-doped BaFe2As2 on TiO2-terminated SrTiO3 is a tetragonal structure with an atomically sharp interface and with an initial Ba layer. In contrast, Co-doped BaFe2As2 on SrO-terminated SrTiO3 has a monoclinic distortion and a BaFeO3-x initial layer. Furthermore, the superconducting transition temperature of Co-doped BaFe2As2 ultrathin films on TiO2-terminated SrTiO3 is significantly higher than that on SrO-terminated SrTiO3, which we attribute to shaper interfaces with no lattice distortions. This study allows the design of the interfacial atomic configurations and the effects of the interface on superconductivity in Fe-based superconductors.",
author = "Kang, {Jong Hoon} and Lin Xie and Yi Wang and Hyungwoo Lee and Neil Campbell and Jianyi Jiang and Ryan, {Philip J.} and Keavney, {David J.} and Lee, {Jung Woo} and Kim, {Tae Heon} and Xiaoqing Pan and Chen, {Long Qing} and Hellstrom, {Eric E.} and Rzchowski, {Mark S.} and Liu, {Zi Kui} and Eom, {Chang Beom}",
note = "Funding Information: This work was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences (BES), under award number DE-FG02-06ER46327. The work at Penn State was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Award DE-FG02-07ER46417 (Y.W. and L.Q.C) and by National Science Foundation (NSF) through Grant No. CHE-1230924 (Z.K.L.). First-principles calculations were carried out on the resources of NERSC supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. The work at UC Irvine was supported by the Department of Energy (DOE), Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Grant DE-SC0014430. The work at the National High Magnetic Laboratory was supported by National Science Foundation through grant No. DMR-1306785, DMR-1157490 and DMR-1644779 and by the State of Florida, USA. Publisher Copyright: {\textcopyright} 2018 American Chemical Society.",
year = "2018",
month = oct,
day = "10",
doi = "10.1021/acs.nanolett.8b02704",
language = "English (US)",
volume = "18",
pages = "6347--6352",
journal = "Nano Letters",
issn = "1530-6984",
publisher = "American Chemical Society",
number = "10",
}