Synthesis of Tl-2223 films, and their, microstructures, superconducting, magnetic, and microwave properties

Abstract

Tl-2223 films were fabricated on LaAlO3 (001) substrates using a two-stage rapid heating approach. Comprehensive characterization confirmed the presence of a pure phase, good epitaxy, and regular texture in the synthesized Tl-2223 films, which exhibited promising properties for practical applications, including an exceptionally high Tc of 118 K, high critical current density (Jc) of 3.54 MA/cm2 (0 T, 77 K), and ultralow microwave surface resistance (Rs) of 129 mΩ. In the absence of an applied magnetic field, the Jc values attained 105 and 104 A/cm2 at 95 and 105 K, respectively. The Hall effect was measured over a wide temperature range of 70–130 K, and the anomalous Hall effect corresponding to the negative swing of the Hall resistivity was observed at a low magnetic field. The Hall coefficient RH was positive in a wide temperature region, verifying the presence of hole carriers. In low- and high-temperature regions, the Jc value and relaxation time of the normal carriers had a negligible and significant influence on Rs, respectively. This study contributes to the characterization of Tl-based films and the analysis of their physical properties for fundamental research and practical applications.