[Bi_(1-x)(Sn_(0.5)Pb_(0.5))_x]_2Sr_2CaCu_2O_y材料的X-ray衍射研究  

X-ray DIFFRACTION STUDY ON [ Bi_(1-x)( Sn_(0．5)Pb_(0．5)_x]_2Sr_2CaCu_2O_y

作　　者：熊小涛[1] 李阳[1] 马庆珠[1] 曹国辉[1] 

机构地区：[1]北京科技大学材料物理系,100083

出　　处：《陶瓷学报》1997年第2期118-122,共5页Journal of Ceramics

摘　　要：以X射线物相分析为主要实验手段，并结合正电子寿命谱和多普勒展宽谱和电阻测量，系统地研究了在不同的锡（铅）掺杂量下，Bi－2212超导相结构细节及电子态的变化。在低掺杂时，Sn^(4+)优先占据Bi位．导致了载流子浓度的提高和层间耦合的加强，有利于超导转变温度的提高。随着掺杂浓度的提高，少量Sn将进入CuO_2层，致使其完整性被破坏；同时有更多的杂相拆出，对材料的超导电性有破坏作用。Investigation on the effect of Sn/Pb - dopped Bi - 2212 superconductors has been canied out by the X - raydiffraction, together with simultaneous measurements of the spectra Of POsitron annihilation lifetime and positronDoppler broadening. The results of samples with different dopping level show that the occupati0n of Sn atoms on Bisites. At weak dopping level, Sn dopping results in a enhancement of cooperation between layers and increment of su-perconducting transition temperature. At the strong dopping level, Sn atoms occupy the sites of Cu - O layers, and atthe same time, the other nonsuperconducting phases appear, which results in a decline of the superconducting transi-tion temperature.

关 键 词：铋系2212相 X射线衍射 锡(铅)掺杂 超导 

分 类 号：TM262.06[一般工业技术—材料科学与工程]