Eu掺杂YBa_2Cu_3O_(7-δ)高温超导单晶的制备与研究

The Preparation and Study of Eu-doped YBa_2Cu_3O_(7-δ)(Y-123) high-T_C Superconducting Single Crystals

本文利用自助熔剂法成功制备了一系列Eu含量不同的Y1-xEuxBa2Cu3O7-δ(x=0.2,0.3,0.4,0.5,0.6,0.7,0.8,0.9,1.0)高温超导单晶样品.实验中使用了ZrO2坩埚,有效地避免了以往Al2O3坩埚在高温下对单晶的污染.X射线衍射(XRD)分析表明,所有单晶样品均为Y-123结构.此外,本文还利用扫描电子显微镜(SEM)在单晶的(0 0l)面观察到了圆形螺旋位错,并对掺杂引起的晶格失配和螺旋位错生长机制进行了分析和讨论.

A series of single crystals with starting composition Y1-xEuxBa2Cu3O7-δ （x = 0.2,0.3,0.4, 0.5,0.6,0.7,0.8,0.9,1.0） were grown by the self-flux method. Contamination of Al2O3 crucibles was avoided by using ZrO2 crucibles. The XRD analysis shows that all the samples have the Y-123 structure. Furthermore, the round screw dislocation are observed on （0 0 l） surface of the single crystal samples by scanning electron microscopy （SEM）. The growth mechanism of the round screw dislocation and the lattice mismatch causing by the doping have been analyzed and discussed in this paper.