Effects of Bi and Si substitutions on (Tl0.5Bi0.5-xSix)Sr2CaCu2O7 superconductor. (January 2020)

• Record Type: Journal Article
• Authors: Zubair-Asyraf, J.M.; Ilhamsyah, A.B.P.; Abd-Shukor, R.
• Is Part Of: Cryogenics. Volume 105(2020)
• Publication Date: 2020-01
• Subjects: Tl-1212 phase -- Ac susceptibility -- Microstructure -- Critical current density; Low temperature engineering -- Periodicals; Low temperature research -- Periodicals; 536.56
• DOI: 10.1016/j.cryogenics.2019.103011
• Languages: English
• ISSNs: 0011-2275

Abstract

Highlights: A superconductor – Si substituted Tl-1212 phase is reported. Enhance flux pinning was observed with Si substitution. Si did not suppress transition temperature for low-level addition ( x ≤ 0.4) Abstract: The effects of Bi and Si substitutions on the superconducting properties of (T10.5 Bi0.5- x Si x )Sr2 CaCu2 O7 (Tl-1212) for x = 0 to 0.5 were studied. The samples were prepared by the solid-state reaction method. X-ray diffraction patterns showed that lower substitution ( x ≤ 0.2) of Si did not affect the formation of Tl-1212 phase. The temperature-dependent electrical resistance measurements showed that the onset transition temperature, T c-onset and zero transition temperature, T c-zero for x = 0–0.4 samples was between 91 and 96 K, and 78 and 81 K, respectively. AC susceptibility measurements showed transition temperature, T c χ' between 82 and 90 K. The peak temperature, T p of the imaginary part of the susceptibility, χ" shifted to higher temperatures for x = 0 to 0.3 indicating enhancement of flux pinning and intergranular coupling. Further substitution of Si ( x = 0.5) destroyed superconductivity of the Tl-1212 phase demonstrating that although Si can fully substitute Bi at Tl site and form majority (60%) Tl-1212 phase, superconductivity was not achieved. This work showed that Si could act as flux pinning centers for Tl-1212 high-temperature superconductor for low-level substitutions.