Author(s)

A. N. Fouda^1,2*

¹Physics Department, Rabigh College of Science and Arts, King Abdulaziz University, Jedda, Saudi Arabia.
²Physics Department, Faculty of Science, Suez Canal University, Ismailia, Egypt.

The effect of La doping on the transport properties and superconducting characterizations of YBa₂Cu₃O_7-δ was investigated. High quality YBa₂(Cu_1-xLa_x)₃O_7-δ superconductor was synthesized with La content of x = 0.00, 0.02, 0.04 and 0.06. The structure and surface morphology were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements. The best superconducting properties can be obtained for substitution of Cu by La concentration within a distinct range (x = 0.02, 0.04). The highest superconducting transition temperature T_c (≈90 K), sharpest transition to superconductivity (ΔT = 5 K) and lowest electrical resistivity (ρ = 9.2 μΩ·cm) correspond to the composition with x = 0.02. Depression and degradation of the superconducting state as (x) increases to 0.06 were observed. Excess dopant of La (x = 0.06) results in a strong decoupling of chains and planes whereas optimal La doping (x = 0.02, x = 0.04) accumulates around the grain, beside the effect of hole filling within this range can adopt an alternate route to extensive oxygen anneal.

Superconductors, X-Ray Diffraction, Transport Properties, Microstructure

Fouda, A. (2018) Effect of Substituting a Fraction of Cu by La on the Transport Properties of YBa₂(Cu_1−xLa_x)₃O_7−δ Superconductor (0 ≤ x ≤ 0.06). Materials Sciences and Applications, 9, 829-836. doi: 10.4236/msa.2018.910059.