TY - JOUR
T1 - Electric and magnetic properties of epitaxial Fe2-xTixO3+δ films
AU - Fujii, T.
AU - Ayama, K.
AU - Nakanishi, M.
AU - Sohma, M.
AU - Kawaguchi, K.
AU - Takada, Jun
N1 - Funding Information:
The authors acknowledge Dr. S. Prasanna for her cooperation in UHV film deposition. This work was financially supported by grant-in-aid from Ministry of Education, Science, Sports and Culture, Japan and Mazda Foundation's Research Grant.
PY - 2000
Y1 - 2000
N2 - Solid solution films of the α-Fe2O3-FeTiO3 series are one of the candidates for noble half-metallic oxides. They were epitaxially formed on α-Al2O3(001) single crystalline substrates by O2-reactive evaporation method. The Fe2-xTixO3+δ films prepared at higher TS=973 K and with larger Ti content x ≥ 0.4 had the ilmenite structure with R3̄ symmetry. Other films at lower TS or with smaller x possessed the corundum structure with R3̄c. Only the films with R3̄ symmetry had large ferrimagnetic moments, though the observed spontaneous magnetization was less than half of the ideal value expected from the fully ordered structure. Room temperature resistivity of intermediate composites dropped to 10-1Ωcm due to the formation of the mixed valence states between Fe2+ and Fe3+. However the Fe2+ content of the films was rather small as compared with stoichiometric Fe2-xTixO3. The Ti-rich films had large oxygen nonstoichiometry of about δ=0.3.
AB - Solid solution films of the α-Fe2O3-FeTiO3 series are one of the candidates for noble half-metallic oxides. They were epitaxially formed on α-Al2O3(001) single crystalline substrates by O2-reactive evaporation method. The Fe2-xTixO3+δ films prepared at higher TS=973 K and with larger Ti content x ≥ 0.4 had the ilmenite structure with R3̄ symmetry. Other films at lower TS or with smaller x possessed the corundum structure with R3̄c. Only the films with R3̄ symmetry had large ferrimagnetic moments, though the observed spontaneous magnetization was less than half of the ideal value expected from the fully ordered structure. Room temperature resistivity of intermediate composites dropped to 10-1Ωcm due to the formation of the mixed valence states between Fe2+ and Fe3+. However the Fe2+ content of the films was rather small as compared with stoichiometric Fe2-xTixO3. The Ti-rich films had large oxygen nonstoichiometry of about δ=0.3.
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U2 - 10.1557/PROC-623-191
DO - 10.1557/PROC-623-191
M3 - Article
AN - SCOPUS:0034446006
VL - 623
SP - 191
EP - 196
JO - Materials Research Society Symposium - Proceedings
JF - Materials Research Society Symposium - Proceedings
SN - 0272-9172
ER -