零电阻为106.5K的单相超导化合物Bi_(1.65)Pb_(0.35)Sr_2Ca_2Cu_3O_y的制备与超导电性  

PREPARATION AND SUPERCONDUCTIVITY OF SINGLE PHASE Bi_(1.65)Pb_(0.35)Sr_2Ca_2Cu_3O_y WITH ZERO RESISTANCE TEMPERATURE 106.5K

作　　者：王顺喜[1] 陈仙辉[2] 夏健生[1] 沙健[1] 危洪斌 马骏[1] 陈祖耀[2] 钱逸泰[2] 张其瑞[1] 

机构地区：[1]中国科学技术大学物理系,合肥230026 [2]中国科学技术大学应用化学系,合肥230026

出　　处：《物理学报》1990年第4期661-666,共6页Acta Physica Sinica

基　　金：国家自然科学基金部分资助的课题

摘　　要：采用固相反应法合成了名义组份为Bi_(2-x)Pb_xSr_2Ca_2Cu_3O_y(x=0.30;0.35;0.40;0.45)的样品。对样品进行了物相和结构分析,同时测量了电阻-温度关系和直流磁化率。结果表明:x=0.35的样品为单相材料,X射线相分析和电子衍射表明其相结构类似2223相,为四方结构,其晶格常数为a=b=5.414A,c=37.106A,且沿a,b两个方向都观察到调制结构。电阻和直流磁化率测量结果显示:在温度高于50K以上,仅存在一个 107K超导相。此外,单相材料的制备条件(组分、烧结温度、室温下淬火及淬火速率)非常苛刻。如同1-2-3相材料一样,氧含量不仅影响样品的成相规律、零电阻温度,而且还严重影响其正常态的输运性质。Samples with nominal composition Bi2-xPb_xSr2Ca2Cu3Oy (x = 0.30;0.35;0.40;0.45) have been prepared by solid state reaction. Phase and structure analyses have been performed, and the resistance-temperature relation and dc susceptibility have also been measured. The results show that the sample with x = 0.35 is a single-phase material. X-ray analysis and electron differaction indicate that its phase structure is similar to that of 2223 phase, it is tetragonal with a = b = 5.414 A, c = 37.106 A, we observed also the modulated structure along a and b. The results of resistance-temperature and dc susceptibility measurement show that, when T = 50 K, there is only one superconducting phase of 107K. In addition, we find that the preparation condition of the single-phase material (composition, sintering temperature and the quenching rate) is stringent. Like the 1-2-3 phase material, the oxygen content not only influences the phase, zero-resistance temperature of the sample, but also influences the transport property of normal state.

关 键 词：零电阻 单相 超导化合物 超导电性 

分 类 号：TM262[一般工业技术—材料科学与工程]