Effect of Silver Addition on the New Y<sub>3</sub>Ba<sub>8</sub>Cu<sub>11</sub>O<sub>x</sub> Superconductors

Abstract

The Y3-8-11 superconductors and silver composite superconductors were synthesized by solid state reaction. The standard four probes method was used to measure the critical temperature (Tc), and the XRD technique (FULLPROF PROGRAM) was used to determine the lattice parameters, space group and phase compositions. It was found that the pure Y3-8-11 has the lowest Tc onset about 95 K, and the more silver doped concentration, have the higher Tc offset and Tc onset. The samples have both superconducting phase and non-superconducting phase. The silver doped samples have higher superconducting phase. The Pmmm space group was corresponding as to superconducting phase. The non-superconducting phase exhibite in Y211 and BaCuO2 with Pbnm and Im-3m, respectively. The surface of the silver doped sample is much smoother and denser compared to the undoped samples without impurities.