TY - JOUR
T1 - Optical spectroscopy study of modifications induced in cerium dioxide by electron and ion irradiations
AU - Costantini, Jean Marc
AU - Gutierrez, Gaëlle
AU - Watanabe, Hideo
AU - Yasuda, Kazuhiro
AU - Takaki, Seiya
AU - Lelong, Gérald
AU - Guillaumet, Maxime
AU - Weber, William J.
N1 - Funding Information:
We thank the French EMIR network for supporting this research programme. The authors are also indebted to Bruno Boizot and Olivier Cavani (École Polytechnique, Palaiseau, France) for their help during the electron irradiations. One of the authors (W. J. W.) was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Science & Engineering Division. This work was also supported by JSPS KAKENHI with a grant number of JP16K06961. The CeO2 thin films were grown at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Ion irradiation was performed under the Join Research Program at RIAM of Kyushu University.
Funding Information:
This work was also supported by JSPS (Japan Society for the Promotion of Science) KAKENHI with a grant number of JP16K06961.
Funding Information:
This work was also supported by JSPS (Japan Society for the Promotion of Science) KAKENHI with a grant number of JP16K06961. We thank the French EMIR network for supporting this research programme. The authors are also indebted to Bruno Boizot and Olivier Cavani (?cole Polytechnique, Palaiseau, France) for their help during the electron irradiations. One of the authors (W.?J.?W.) was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Science & Engineering Division. This work was also supported by JSPS KAKENHI with a grant number of JP16K06961. The CeO2 thin films were grown at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Ion irradiation was performed under the Join Research Program at RIAM of Kyushu University.
Publisher Copyright:
© 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group.
PY - 2019/7/18
Y1 - 2019/7/18
N2 - UV-visible absorption spectroscopy and Raman spectroscopy were used to study damage production in cerium dioxide epitaxial films and polycrystalline sintered samples after irradiation with electrons for three energies to span the threshold displacement energies of cerium and oxygen atoms, and 2.4-MeV Cu ions. Neither amorphization nor specific colour-centre bands were detected. Evolutions of the refractive index were derived from the interference fringes in the optical transmission spectra of epilayers after irradiation. No significant change of the refractive index occurred for the 1.0-MeV electron irradiation, whereas a maximum decrease by 28 ± 8% was deduced for the 1.4-MeV and 2.5-MeV energies. These modifications are consistent with ballistic damage on the cerium sublattice for high electron energies producing Ce3+ ions. However, no significant change of refractive index was found for the Cu ion irradiation. This likely stems from the high rate of Frenkel pair recombination in the collision cascades induced by more energetic recoils than for the electron irradiations, combined with electronic excitations and hole capture on Ce3+ ions. This study reveals modifications of the electronic structure upon irradiation that could take place in other non-amorphizable oxide systems.
AB - UV-visible absorption spectroscopy and Raman spectroscopy were used to study damage production in cerium dioxide epitaxial films and polycrystalline sintered samples after irradiation with electrons for three energies to span the threshold displacement energies of cerium and oxygen atoms, and 2.4-MeV Cu ions. Neither amorphization nor specific colour-centre bands were detected. Evolutions of the refractive index were derived from the interference fringes in the optical transmission spectra of epilayers after irradiation. No significant change of the refractive index occurred for the 1.0-MeV electron irradiation, whereas a maximum decrease by 28 ± 8% was deduced for the 1.4-MeV and 2.5-MeV energies. These modifications are consistent with ballistic damage on the cerium sublattice for high electron energies producing Ce3+ ions. However, no significant change of refractive index was found for the Cu ion irradiation. This likely stems from the high rate of Frenkel pair recombination in the collision cascades induced by more energetic recoils than for the electron irradiations, combined with electronic excitations and hole capture on Ce3+ ions. This study reveals modifications of the electronic structure upon irradiation that could take place in other non-amorphizable oxide systems.
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U2 - 10.1080/14786435.2019.1599145
DO - 10.1080/14786435.2019.1599145
M3 - Article
AN - SCOPUS:85063981202
SN - 1478-6435
VL - 99
SP - 1695
EP - 1714
JO - Philosophical Magazine
JF - Philosophical Magazine
IS - 14
ER -