抄録
We present a photoemission and x-ray-absorption study of the misfit-layered (Bi,Pb)-Sr-Co-O compounds which have a Co-O triangular lattice with a mixed valence of Co3+ and Co4+. The valence-band photoemission as well as the O 1s and Co 2p x-ray absorption spectra indicate that Co3+ and Co4+ have the low-spin t2g6 and t2g5 configurations, respectively. The angle-resolved photoemission spectra show that the dispersion of the t2g feature is very small compared to its width at each angle, suggesting that the electron-lattice coupling energy is much larger than the kinetic energy of the t2g electrons and that the carriers in the Co-O triangular lattice are essentially polarons formed by Co4+ in the nonmagnetic Co3+ background.
本文言語 | English |
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論文番号 | 115104 |
ページ(範囲) | 1151041-1151047 |
ページ数 | 7 |
ジャーナル | Physical Review B - Condensed Matter and Materials Physics |
巻 | 64 |
号 | 11 |
出版ステータス | Published - 2001 9月 15 |
外部発表 | はい |
ASJC Scopus subject areas
- 電子材料、光学材料、および磁性材料
- 凝縮系物理学