Bulk 2a×2b×c superstructure in TCNQ-treated (Bi, Pb)-2223 cuprates

✍ Scribed by C.-J. Liu; X.-J. Wu; H. Yamauchi

• Book ID: 103948793
• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 426 KB
• Volume: 231
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(94)90646-7

✦ Synopsis

By reacting (Bi, Pb)-2223 cuprate superconductors with TCNQ (7,7,8,8-tetracyanoquinodimethane) in a sealed and evacuated pyrex ampoule at 300"C for 14 days, we have observed a superstructure of 2a×2bxc in a bulk form according to X-ray diffraction and transmission electron microscope analyses. The origin of the 2a X 2b X c superstructure could be attributed to an ordering of oxygen vacancies in the CuO2 layers and also likely in the SrO layers. Electrical conductivity of this TCNQ treated (Bi, Pb)-2223 cuprate shows a metal-like temperature dependence with high resistivity ( 102~ 103 ~ cm), and a relatively rapid resistivity drop at ca. 11.7 K.