论文部分内容阅读
继 YBa_2Cu_3O_(7-a)后,人们又发现了一种新的高Tc超导氧化物Bi-Sr-Ca-Cu-O,并对其结构进行了初步的研究,上述工作中均报道了粉末烧制的Bi-Sr-Ca-Cu-O体系的超导样品中的相结构。本文对具有Tc=76k的Bi-Sr-Ca-Cu-O体系超导样品中的两个相进行了透射电镜研究,观察到一个新的无公度相。将块状样品研磨成微小颗粒再用喷了金的微筛捞起,制成透射电镜样品。所用电镜是H—800分析电镜。透射电镜观察表明,样品中主要存在两个相,其中之一是含Bi较少的相,我们对它作倾动晶体电子衍射,根据电子衍射图可构造出倒易点阵。计算表明,在误差范围内,(?)与(?)垂直。从这个倒易点阵可知此相属体心正交,点阵参数为a=0.850±
Following YBa_2Cu_3O_ (7-a), a new high Tc superconducting oxide Bi-Sr-Ca-Cu-O has been discovered and its structure has been studied. In the above work, Phase structure in the superconducting sample of the fired Bi-Sr-Ca-Cu-O system. In this paper, two phases in the superconducting sample of Bi-Sr-Ca-Cu-O system with Tc = 76k were investigated by transmission electron microscopy, and a new phase was observed. The massive sample was ground into tiny particles and then sprayed with gold microscopic sieve picked up, made of transmission electron microscopy samples. The electron microscope is H-800 analytical microscope. Transmission electron microscopy showed that there are two main phases in the sample, one of them is a phase containing less Bi, we tilt it crystal electron diffraction, according to the electron diffraction pattern can be constructed reciprocal lattice. Calculations show that (?) Is perpendicular to (?) Within the error range. From this reciprocal lattice we can see that this phase belongs to the body orthogonal, lattice parameters a = 0.850 ±