Abstract
Chemical sol-gel route was opted for synthesis of chromium (Cr) nanoparticles (NPs) and solid-state reaction method was used to synthesize the superconducting (CuTl)(0.5)Ba2Ca2Cu3O10-delta {(CuTl)-1223} phase. The desired (Cr)(x)/(CuTl)-1223; x = 0-2.0 wt% nanoparticles-superconductor composites were obtained by the incorporation of Cr NPs in the host superconducting (CuTl)-1223 matrix. The crystal structure along with the phase purity was explored by X-rays diffraction (XRD) and the transport properties were studied by the dc-resistivity and dielectric measurements of these composites. The crystal structure of these composites was found un-altered, which indicated the presence of Cr NPs at the inter-granular regions of the host CuTl-1223 superconducting matrix. The suppression in superconducting transport properties of CuTl-1223 superconducting phase could be associated to the reduction of superconducting volume fraction after the inclusion of Cr NPs. The effects of Cr NPs on the ac-conduction process in (CuTl)-1223 phase were investigated via frequency dependent dielectric measurements at different operating temperatures.