The effect of nano-sized metallic Au addition on structural and magnetic properties of Bi1.8Sr2 AuxCa1.1Cu2.1Oy (Bi-2212) ceramics

In this paper, we present the superconducting properties of nano-sized metallic Au doped Bi-2212 ceramics. Polycrystalline samples of Bi1.8Sr2AuxCa1.1Cu2.1Oy (x=0.0, 0.05, 0.1 and 0.2) superconductor have been synthesized by the conventional solid state reaction method. The phases as well as electric and magnetic properties have been characterized by XRD, SEM, DC resistivity, and magnetic hysteresis measurements (M-H). It has been observed that Tc (offset) values increase gradually as nano-sized Au content is increased. X-ray diffraction results indicated that nano-sized Au doping with x range from 0 to 0.2 did not provide its incorporation with any elements in the unit cell of the Bi-2212 matrix. M-H measurements were performed at T=10 K. In addition, Jc values of the samples were calculated from their magnetic hysteresis loops using the Bean's model. It has been observed that the enhancement of Jc was as high as 4.3×104 A/cm2 in 1.95 T at 10 K for Bi1.8Sr2 Au0.2Ca1.1Cu2.1Oy sample with x=0.2 Au addition when compared to the undoped sample that is considered as important for the enhancement of flux pinning in high magnetic fields.