Structural and superconducting properties in Y_(0.6)Gd_(0.4)Ba_2(Nb)Cu_3O_(7-y) cuprates doped with niobium

作     者：M. Yilmaz O. Dogan 

作者机构：A. K. Education Faculty Department of Physics Konya University 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2012年第30卷第3期

页      面：241-244页

核心收录：

学科分类：081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 070301[理学-无机化学] 

基　　金：Project supported by the Council of the Scientific Research Projects at Konya University 

主　　题：Y0.6Gd0.4Ba2Cu3O7 y cuprates Gd and Nb co doping structural and superconducting properties rare earths 

摘      要：Polycrystalline YBa2Cu3O7-y （YBCO） and Y0.6Gd0.4Ba2-xNbxCu3O7-y （YGBNCO） compounds with 0≤x≤0.225 were synthesized using standard solid state reaction technique. The structure for all samples was characterized by X-ray difference （XRD） and scanning electron microscopy （SEM）. The transport properties were measured by the （FPP） method in the temperature range from 70 to 130 K. As the Nb content in the samples increased, a diffused phase indicating a niobium perovskite phase and a small amount of unidentified phase appeared. With the increase of Nb content, the superconducting transition temperature Tconset increased slowly with x≤0.125, and then it remained unchanged or slowly decreased with 0.125≤x≤0.225. It could be found that there was a slow decrease of zero-resistance temperature, Tcoffset, with the increase of Nb content. The larger transition width might result from the YBa2NbO6 phase, impurity and unidentified phases of the sample due to the Nb doping.