Charge transfer gap for T′-RE2CuO4 and T-La2CuO4 as estimated from Madelung potential calculations

被引:8
作者
Tsukada, A.
Shibata, H.
Noda, M.
Yamamoto, H.
Naito, M.
机构
[1] Tokyo Univ Agr & Technol, Dept Appl Phys, Naito Lab, Koganei, Tokyo 1848588, Japan
[2] NTT Corp, Basic Res Labs, Kanagawa 2430198, Japan
[3] Tokyo Univ Sci, Chiba 2788510, Japan
来源
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS | 2006年 / 445卷
关键词
mother compound; T '-structure; charge-transfer gap; Madelung potential;
D O I
10.1016/j.physc.2006.03.087
中图分类号
O59 [应用物理学];
学科分类号
摘要
T '-RE2CUO4 (RE: rare-earth element), after appropriate "reduction", has fairly high conductivity and also exhibits clear Fermi edge in photoemission spectroscopy. To clarify the origin of conductivity in the T ' mother compounds, we evaluated the unscreened charge-transfer gap (Delta(0)) for T '-RE2CUO4 and T-La2CuO4. The Delta(0) value for T '-compounds almost linearly decreases with increasing the ionic radius of RE from 12.24 eV for T '-Tm2CuO4 to 9.90 eV for T '-La2CuO4. The results qualitatively explain metallic conductivity in T '-RE2CuO4 for large RE. (c) 2006 Published by Elsevier B.V.
引用
收藏
页码:94 / 96
页数:3
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