Diese Seite ist aus Gründen der Barrierefreiheit optimiert für aktuelle Browser. Sollten Sie einen älteren Browser verwenden, kann es zu Einschränkungen der Darstellung und Benutzbarkeit der Website kommen!
Geophysics Homepage
Search:
Log in
print

Insights into the structural, electronic and magnetic properties of Fe2-xTixO3/Fe2O3 thin films with x = 0.44 grown on Al2O3 (0001)

Dennenwaldt, T, et al. (2015), Insights into the structural, electronic and magnetic properties of Fe2-xTixO3/Fe2O3 thin films with x = 0.44 grown on Al2O3 (0001), J. Mater. Sci., 50(1), 122-137, doi:10.1007/s10853-014-8572-x.

Abstract
The interface between hematite (α-Fe 2 III O3) and ilmenite (FeIITiO3), a weak ferrimagnet and an antiferromagnet, respectively, has been suggested to be strongly ferrimagnetic due to the formation of a mixed valence layer of Fe2+/Fe3+ (1:1 ratio) caused by compensation of charge mismatch at the chemically abrupt boundary. Here, we report for the first time direct experimental evidence for a chemically distinct layer emerging at heterointerfaces in the hematite—Ti-doped-hematite system. Using molecular beam epitaxy, we have grown thin films (~25 nm thickness) of α-Fe2O3 on α-Al2O3 (0001) substrates, which were capped with a ~25 nm thick Fe2−x Ti x O3 layer (x = 0.44). An additional 3 nm cap of α-Fe2O3 was deposited on top. The films were structurally characterized in situ with surface X-ray diffraction, which showed a partial low index orientation relationship between film and substrate in terms of the [0001] axis and revealed two predominant domains with (0001)Fe2O3||(0001)Al2O3, one with [101¯0]Fe2O3||[101¯0]Al2O3, and a twin domain with [011¯0]Fe2O3||[101¯0]Al2O3. Electron energy loss spectroscopy profiles across the Fe2−x Ti x O3/Fe2O3 interface show that Fe2+/Fe3+ ratios peak right at the interface. This strongly suggests the formation of a chemically distinct interface layer, which might also be magnetically distinct as indicated by the observed magnetic enhancement in the Fe2−x Ti x O3/α-Fe2O3/Al2O3 system compared to the pure α-Fe2O3/Al2O3 system.
Further information
BibTeX
@article{id2030,
  author = {T Dennenwaldt and M  L{\"u}bbe and M Winklhofer and A M{\"u}ller and M D{\"o}blinger and H Sadat Nabi and M Gandman and T Cohen-Hyams and WD  Kaplan and W Moritz and R Pentcheva and C Scheu},
  journal = {J. Mater. Sci.},
  month = {jan},
  number = {1},
  pages = {122-137},
  title = {{Insights into the structural, electronic and magnetic properties of Fe2-xTixO3/Fe2O3 thin films with x = 0.44 grown on Al2O3 (0001)}},
  volume = {50},
  year = {2015},
  url = {http://link.springer.com/article/10.1007%2Fs10853-014-8572-x},
  doi = {10.1007/s10853-014-8572-x},
}
EndNote
%0 Journal Article
%A Dennenwaldt, T
%A Lübbe, M 
%A Winklhofer, M
%A Müller, A
%A Döblinger, M
%A Sadat Nabi, H
%A Gandman, M
%A Cohen-Hyams, T
%A Kaplan, WD 
%A Moritz, W
%A Pentcheva, R
%A Scheu, C
%D 2015
%N 1
%V 50
%J J. Mater. Sci.
%P 122-137
%T Insights into the structural, electronic and magnetic properties of Fe2-xTixO3/Fe2O3 thin films with x = 0.44 grown on Al2O3 (0001)
%U http://link.springer.com/article/10.1007%2Fs10853-014-8572-x
%8 jan
ImprintPrivacy PolicyContact
Printed 25. Aug 2019 09:06