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ID 18667
本文ファイル
著者
Fukuda, H.
Fujii, Hironobu
Kamura, H.
Hasegawa, Yuichi
Kikugawa, Naoki
Fujita, Toshizo
抄録(英)
We studied the dilute substitution effect on magnetic and transport properties in an unstable ferromagnet CeFe2 with a C15 cubic Laves-phase structure. In the Co substitution system Ce(Fe1-xCox)2 with x≤0.10, while the Curie temperature T c decreases with increasing the Co concentration, an antiferromagnetic ordering appears in the low temperature region for x≥0.05, and the transition temperature T o from ferromagnetic to antiferromagnetic states monotonously increases with increasing the Co concentration. On the other hand, in the Sc substitution system (Ce1-ySCy)Fe2 with y≤0.10, both the Curie temperature T c and saturation magnetization M s at 4.2 K gradually increase with increasing the Sc concentration. Despite the decrease in lattice parameter upon substitution in both the systems, an antiferromagnetic ground state is stabilized in Ce(Fe1-xCox)2, whereas a ferromagnetic ground state is stabilized in (Ce1-yScy)Fe2. These results indicate that the Fe 3d–Fe 3d ferromagnetic exchange interaction and the antiferromagnetic spin correlation arising from the Ce4f–Fe3d hybridization compete in CeFe2, and the enhancement/depression of the 4f-3d hybridization effect might make the ferromagnetic ground state in CeFe2 unstable/stable. Furthermore, Ce(Fe1-xCox)2 exhibited a negative giant magnetoresistance reaching about δρ/ρ= ∼60–65 % at 4.2 K, which is accompanied by a metamagnetic transition from antiferromagnetic to ferromagnetic states. The giant magnetoresistance effect is originated from the reconstruction of Fermi surface due to the collapse of the superzone gap after the metamagnetic transition.
掲載誌名
Physical Review B - Condensed Matter and Materials Physics
63巻
5号
開始ページ
054405-1
終了ページ
054405-9
出版年月日
2001-01-03
出版者
American Physical Society
ISSN
0163-1829
NCID
出版者DOI
言語
英語
NII資源タイプ
学術雑誌論文
広大資料タイプ
学術雑誌論文
DCMIタイプ
text
フォーマット
application/pdf
著者版フラグ
publisher
権利情報
Copyright (c) 2001 American Physical Society.
関連情報URL
部局名
先端物質科学研究科