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ID 18720
本文ファイル
著者
Matsuhata, Hirofumi
Iga, Fumitoshi
Tsubota, Masami
Nakano, Toshihiro
Kato, Kenichi
抄録(英)
Structural changes in Y1-xCaxTiO3 (x=0.37, 0.39 and 0.41) during a transition from an insulator-to-metal were investigated by transmission electron microscopy. In a specimen for x=0.39, on cooling a transition from orthorhombic to monoclinic lattice was observed first. The onset of this transition was not certain, but the monoclinic lattice was clearly observed at 170 K. On further cooling to 140 K, approximately the metalinsulator transition temperature, an introduction of strain to this monoclinic phase was observed. Below 140 K a state of phase separation, with growth of domains, was observed. In the insulator specimen for x=0.37 the transition from orthorhombic to monoclinic lattice was observed similarly to the case of x=0.39, but no phase separation was observed in the range from room temperature to 110 K. In the case for x=0.41, the phase separation was also observed on cooling, but transition temperature of the phase separation is lower than that reported by x-ray diffraction. The phase separation observed presently for 0.39 and 0.41 is considered to be a kind of electrical phase separation, which drives the appearance of the metallic state at low temperatures. This is the first report on observation of separated domains on the electrical phase separation associated with the metal-insulator transition in paramagnetic Y1-xCaxTiO3.
掲載誌名
Physical Review B - Condensed Matter and Materials Physics
70巻
13号
開始ページ
134109-1
終了ページ
134109-6
出版年月日
2004-10-26
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) 2005 American Physical Society.
関連情報URL
部局名
先端物質科学研究科