Effect of Si substitution on the structure and superconductivity of YBa2 (Cu1- x Six)3 O7-δ superconductor (0≤ x ≤ 0.03 )

Résumé

In this research, samples were prepared by using solid state reaction with starting composition YBa2 (Cu3-x Si x) O7-x for x= 0.00, 0.01, 0.02 and 0.03. . The variation of the structural changes of the lattice parameters orthorhombic distortion and strain of YBa2(Cu1-x Six)3O7-δprepared samples as a function of Si concentration (x) within the range of (0 < x ≤ 0.03) were studied, using XRD measurements. Within this range, a, b and c by Miller indices (h k l) should know. the lattice parameters a, b and c are given in the (h, k, l) values calculated from unit cell parameters shows that samples has c-axis orientation and their structure has orthorhombic symmetry. that the structure is orthorhombic with lattice parameters a ≠ b ≠ c. X-ray powder diffraction pattern using Cu-Kα radiation of YBa2Cu3O7−δ (x=0.03) rise in impurity phases can be seen for the Si-doped system. Peaks that belong to different phases YBa2(Cu3-x Si x)O7-x were observed. But, any considerable changes in amplitude of the peaks are not seen in the figure. Si doping drives YBa2Cu3O7-x structure reduces superconductivity. On the other hand, the substitution of Si does not have considerable effect on YBa2Cu3O7-x system.