Suppression of activation energy and superconductivity by the addition of Al{sub 2}O{sub 3} nanoparticles in CuTl-1223 matrix

Journal Article · Wed May 28 00:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4879197· OSTI ID:22304374

Jabbar, Abdul; Qasim, Irfan; Mumtaz, M.; Zubair, M.; Nadeem, K. ^[1]; Khurram, A. A. ^[2]

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1. Materials Research Laboratory, Department of Physics, FBAS, International Islamic University (IIU) Islamabad, Islamabad 44000 (Pakistan)
2. Experimental Physics Labs, National Centre for Physics, Islamabad (Pakistan)

Low anisotropic (Cu{sub 0.5}Tl{sub 0.5})Ba{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10−δ} (CuTl-1223) high T{sub c} superconducting matrix was synthesized by solid-state reaction and Al{sub 2}O{sub 3} nanoparticles were prepared separately by co-precipitation method. Al{sub 2}O{sub 3} nanoparticles were added with different concentrations during the final sintering cycle of CuTl-1223 superconducting matrix to get the required (Al{sub 2}O{sub 3}){sub y}/CuTl-1223, y = 0.0, 0.5, 0.7, 1.0, and 1.5 wt. %, composites. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy, energy dispersive X-ray, and dc-resistivity (ρ) measurements. The activation energy and superconductivity were suppressed with increasing concentration of Al{sub 2}O{sub 3} nanoparticles in (CuTl-1223) matrix. The XRD analysis showed that the addition of Al{sub 2}O{sub 3} nanoparticles did not affect the crystal structure of the parent CuTl-1223 superconducting phase. The suppression of activation energy and superconducting properties is most probably due to weak flux pinning in the samples. The possible reason of weak flux pinning is reduction of weak links and enhanced inter-grain coupling due to the presence of Al{sub 2}O{sub 3} nanoparticles at the grain boundaries. The presence of Al{sub 2}O{sub 3} nanoparticles at the grain boundaries possibly reduced the number of flux pinning centers, which were present in the form of weak links in the pure CuTl-1223 superconducting matrix. The increase in the values of inter-grain coupling (α) deduced from the fluctuation induced conductivity analysis with the increased concentration of Al{sub 2}O{sub 3} nanoparticles is a theoretical evidence of improved inter-grain coupling.

• OSTI ID: 22304374
• Journal Information: Journal of Applied Physics, Vol. 115, Issue 20; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ACTIVATION ENERGY
ALUMINIUM OXIDES
ANISOTROPY
BARIUM COMPOUNDS
CALCIUM COMPOUNDS
COPPER COMPOUNDS
COPRECIPITATION
CRYSTAL STRUCTURE
CUPRATES
FLUCTUATIONS
GRAIN BOUNDARIES
HIGH-TC SUPERCONDUCTORS
MATRIX MATERIALS
NANOPARTICLES
SCANNING ELECTRON MICROSCOPY
SUPERCONDUCTIVITY
THALLIUM COMPOUNDS
X RADIATION
X-RAY DIFFRACTION