Premium
Atmosphere‐Induced Reversible Resistivity Changes in Ca/Y‐Doped Bismuth Iron Garnet Thin Films
Author(s) -
Teurtrie Adrien,
Popova Elena,
Koita Ibrahim,
Chikoidze Ekaterine,
Keller Niels,
Gloter Alexandre,
Bocher Laura
Publication year - 2019
Publication title -
advanced functional materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.069
H-Index - 322
eISSN - 1616-3028
pISSN - 1616-301X
DOI - 10.1002/adfm.201904958
Subject(s) - bismuth , materials science , dopant , doping , electrical resistivity and conductivity , spintronics , faraday effect , condensed matter physics , oxide , nanotechnology , analytical chemistry (journal) , optoelectronics , ferromagnetism , chemistry , metallurgy , electrical engineering , magnetic field , physics , engineering , quantum mechanics , chromatography
Bismuth iron garnet Bi 3 Fe 5 O 12 (BIG) is a multifunctional insulating oxide exhibiting remarkably the largest known Faraday rotation and linear magnetoelectric coupling. Enhancing the electrical conductivity in BIG while preserving its magnetic properties would further widen its range of potential applications in oxitronic devices. Here, a site‐selective codoping strategy in which Ca 2+ and Y 3+ substitute for Bi 3+ is applied. The resulting p‐ and n‐type doped BIG films combine state‐of‐the‐art magneto‐optical properties and semiconducting behaviors above room temperature with rather low resistivity: 40 Ω cm at 450 K is achieved in an n‐type Y‐doped BIG; this is ten orders of magnitude lower than that of Y 3 Fe 5 O 12 . High‐resolution electron spectromicroscopy unveils the complete dopant solubility and the charge compensation mechanisms at the local scale in p‐ and n‐type systems. Oxygen vacancies as intrinsic donors play a key role in the conduction mechanisms of these doped BIG films. On the other hand, a self‐compensation of Ca 2+ with oxygen vacancies tends to limit the conduction in p‐type Ca/Y‐doped BIG. These results highlight the possibility of integrating n‐type and p‐type doped BIG films in spintronic structures as well as their potential use in gas sensing applications.