Abstract
We have investigated the local structure of amorphous oxides in EuO-TiO 2system to understand the mechanism that gives rise to curious ferromagnetic properties recently observed in the system. X-ray absorption spectroscopy has been performed on amorphous EuTiO 3and Eu 2TiO 4thin films prepared by the pulsed-laser-deposition method. The Ti K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) data analyses reveal that the coordination number of Ti 4+ in the amorphous thin films is around 4, which is in sharp contrast to their crystalline counterparts, where Ti 4+ ions are octahedrally coordinated by oxide ions. It is therefore inferred that Ti 4+ acts as a network-forming cation in the random network structure of the amorphous oxides. From the Eu L 3-edge EXAFS data analyses, it is found that the coordination number of Eu 2+ is much lower and the nearest Eu-O bond length is shorter in the amorphous thin films than in the crystalline counterparts. The amorphization-induced enhancement of ferromagnetic interactions observed in the EuO-TiO 2system is discussed in terms of the local environment around Eu 2+ ions.
| Original language | English |
|---|---|
| Pages (from-to) | 716-720 |
| Number of pages | 5 |
| Journal | Journal of the American Ceramic Society |
| Volume | 95 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Feb 1 2012 |
| Externally published | Yes |
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All Science Journal Classification (ASJC) codes
- Ceramics and Composites
- Materials Chemistry
Cite this
Local structure of amorphous EuO-TiO 2thin films probed by x-ray absorption fine structure. / Zong, Yanhua; Fujita, Koji; Akamatsu, Hirofumi; Nakashima, Seisuke; Murai, Shunsuke; Tanaka, Katsuhisa.
In: Journal of the American Ceramic Society, Vol. 95, No. 2, 01.02.2012, p. 716-720.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Local structure of amorphous EuO-TiO 2thin films probed by x-ray absorption fine structure
AU - Zong, Yanhua
AU - Fujita, Koji
AU - Akamatsu, Hirofumi
AU - Nakashima, Seisuke
AU - Murai, Shunsuke
AU - Tanaka, Katsuhisa
PY - 2012/2/1
Y1 - 2012/2/1
N2 - We have investigated the local structure of amorphous oxides in EuO-TiO 2system to understand the mechanism that gives rise to curious ferromagnetic properties recently observed in the system. X-ray absorption spectroscopy has been performed on amorphous EuTiO 3and Eu 2TiO 4thin films prepared by the pulsed-laser-deposition method. The Ti K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) data analyses reveal that the coordination number of Ti 4+ in the amorphous thin films is around 4, which is in sharp contrast to their crystalline counterparts, where Ti 4+ ions are octahedrally coordinated by oxide ions. It is therefore inferred that Ti 4+ acts as a network-forming cation in the random network structure of the amorphous oxides. From the Eu L 3-edge EXAFS data analyses, it is found that the coordination number of Eu 2+ is much lower and the nearest Eu-O bond length is shorter in the amorphous thin films than in the crystalline counterparts. The amorphization-induced enhancement of ferromagnetic interactions observed in the EuO-TiO 2system is discussed in terms of the local environment around Eu 2+ ions.
AB - We have investigated the local structure of amorphous oxides in EuO-TiO 2system to understand the mechanism that gives rise to curious ferromagnetic properties recently observed in the system. X-ray absorption spectroscopy has been performed on amorphous EuTiO 3and Eu 2TiO 4thin films prepared by the pulsed-laser-deposition method. The Ti K-edge X-ray absorption near-edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) data analyses reveal that the coordination number of Ti 4+ in the amorphous thin films is around 4, which is in sharp contrast to their crystalline counterparts, where Ti 4+ ions are octahedrally coordinated by oxide ions. It is therefore inferred that Ti 4+ acts as a network-forming cation in the random network structure of the amorphous oxides. From the Eu L 3-edge EXAFS data analyses, it is found that the coordination number of Eu 2+ is much lower and the nearest Eu-O bond length is shorter in the amorphous thin films than in the crystalline counterparts. The amorphization-induced enhancement of ferromagnetic interactions observed in the EuO-TiO 2system is discussed in terms of the local environment around Eu 2+ ions.
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U2 - 10.1111/j.1551-2916.2011.04849.x
DO - 10.1111/j.1551-2916.2011.04849.x
M3 - Article
VL - 95
SP - 716
EP - 720
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
SN - 0002-7820
IS - 2
ER -