Физика Низких Температур: Том 48, Выпуск 1 (Январь 2022), c. 5-9 ( к оглавлению , назад )
Comparative study of Tl-1223 superconductors prepared by the sol-gel route and solid-state reaction
I. R. Metskhvarishvili1,2, T. E. Lobzhanidze3, G. N. Dgebuadze1, B. G. Bendeliani1, M. R. Metskhvarishvili2, M. Sh. Rusia3
G. R. Giorganashvili1, and V. M. Gabunia1,4
1Ilia Vekua Sukhumi Institute of Physics and Technology, Tbilisi 0186, Georgia
3Ivane Javakhishvili Tbilisi State University, Tbilisi 0179, Georgia
Received June 11, 2021, published online November 25, 2021
This paper presents sol-gel (SG) and solid-state reaction (SSR) pathways to produce multiphase ceramic precursors of BCCO and then the superconducting phase of Tl-1223. The heat treatments showed that to obtain high-purity precursors prepared by SG and SSR methods are sufficient to heat treatments at 915 and 945 °C, respectively. Furthermore, the diamagnetic onset temperature of the superconducting transition for the Tl-1223 samples prepared by precursors SG at 915 °C and SSR at 945 °C is approximately 120 K, and complete screening of applied ac magnetic fields observed at T ≈ 102 and ≈ 94 K, respectively. In addition, the value of the transport critical current density Jc for SSR was 128 A/cm2, whereas for the SG sample it was precisely 174 A/cm2. Thus, we could conclude that using wet chemistry offers some advantages over classical solid-state ceramic processing, significantly better chemical homogeneity, and higher reactivity of the precursor powder.
Key words: Tl-1223 phases, precursors, sol-gel route, solid-state reaction, ac susceptibility.