Y(Ba_(1-x)Gd_x)_2Cu_3O_(7-δ)的临界电流密度特征

多晶样品Y(Ba1-xGdx)2Cu3O7-δ(YBGCO)(x=0.0,0.02,0.03,0.05,0.08,0.10)是由标准固相反应法制备获得。XRD的Rietveld精修显示,Gd成功地部分替代YBa2Cu3O7-δ(YBCO)晶胞中的Ba位。实验结果表明,对于某一固定磁场Y(Ba1-xGdx)2Cu3O7-δ的临界电流密度(Jc)在x=0.05有最大值。此外,尽管YBGCO的超导温度(Tc)明显地单调下降,但微量的Gd掺杂导致磁场中YBGCO的Jc的提高。Jc随着Gd掺杂量不同而变化的特征行为可以认为,是由Gd掺杂引起的两种不同的效果竞争共同作用造成的,即纳米尺度范围内空间分布不均匀性和超导性的变化。

Critical Current Density Characteristic of Y(Ba1-xGdx)2Cu3O7-δ

The poly-crystallized samples of Y(Ba1-xGdx)2Cu3O7-δ with x =0.0,0.02,0.03,0.05,0.08,0.10,were prepared by standard solid state reactions method.X-ray diffraction with Rietveld refinement studies showed that Gd replaced partly Ba in the unit cell.The critical current density(Jc) exhibited a maximum at x=0.05 for Y(Ba1-xGdx)2Cu3O7-δ samples with fixing field.Moreover,slight Gd-doping in YBa2Cu3O7-(YBCO)enhanced Jc by applying the magnetic field,although the superconducting temperature(Tc) decreased slightly.The characteristic behavior of Jc with varying the Gd content can be explained in terms of the competition between two different effects caused by Gd-doping in YBCO: the inhomogeneity of grains distribution in nano-scale and the variation of superconductivity.