Local structure study of T′ cuprate superconductors |
| |
Authors: | H Oyanagi A Tsukada M Naito |
| |
Institution: | a National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan b NTT Basic Research Laboratories, 3-1 Morinosato-Wakamiya, Atsugi, Kanagawa 243-0198, Japan c Tokyo University of Agriculture and Technology, 2-24-6 Nakacho, Koganei-shi, Tokyo 184-8588, Japan |
| |
Abstract: | Undoped T′-type cuprates are believed to be charge transfer (Mott-Hubbard) insulators. Recent observation of undoped superconducting T′-type cuprates suggests half-filling weakly correlated metallic electron states (Tsukada et al.), which is against the fundamental picture. Here we report the local structures of undoped T′-(La3+,Y3+)2CuO4 and doped T′-(La3+,Ce4+)2CuO4 thin-film single crystals by polarized extended X-ray absorption fine structure (EXAS). The in-plane (E//ab) polarized Cu K-EXAFS data shows a remarkable Cu-O bond distance displacement. The broadened Cu-O distribution suggests a large local lattice distortion in T′-type structures, which might influence the electronic structure. |
| |
Keywords: | 61 10 Ht 74 72 &minus h |
本文献已被 ScienceDirect 等数据库收录! |
|