Synthesis of $c$-axis textured CaKFe$_4$As$_4$ superconducting bulk via spark plasma texturing technique

Shigeyuki Ishida; Yoshihisa Kamiya; Yoshinori Tsuchiya; Pavan Kumar Naik Sugali; Yasunori Mawatari; Akira Iyo; Yoshiyuki Yoshida; Hiroshi Eisaki; Kenji Kawashima; Hiraku Ogino

doi:10.1016/j.jallcom.2023.171093

arXiv · 2403.19984

Synthesis of $c$-axis textured CaKFe$_4$As$_4$ superconducting bulk via spark plasma texturing technique

Shigeyuki Ishida·Yoshihisa Kamiya·Yoshinori Tsuchiya·Pavan Kumar Naik Sugali·Yasunori Mawatari·Akira Iyo·Yoshiyuki Yoshida·Hiroshi Eisaki·Kenji Kawashima·Hiraku Ogino

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Abstract

Grain alignment is a key factor that determines the performance of a superconducting bulk. In this study, the spark plasma texturing (SPT) technique was used to fabricate a CaKFe$_4$As$_4$ superconducting bulk. X-ray diffraction and electron backscatter diffraction revealed that the $c$-axes of the CaKFe$_4$As$_4$ grains in the SPT bulk are aligned, demonstrating that the SPT technique is effective in achieving $c$-axis texture. In addition, chemical composition analysis showed that oxide impurities, which affect the grain boundary characteristics that determine the inter-grain critical current density ($J_c$), are randomly distributed in the SPT bulk. Magnetization measurements showed high $J_c$ values of the SPT bulk, reaching 127 kA cm$^{-2}$ and 26 kA cm$^{-2}$ at 4.2 K under a self-field and magnetic field of 5 T, respectively. These results suggest that the SPT technique is a promising approach for obtaining a high-performance superconducting bulk material for high-field applications.

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Shigeyuki Ishida, Yoshihisa Kamiya, Yoshinori Tsuchiya, Pavan Kumar Naik Sugali, Yasunori Mawatari, Akira Iyo, Yoshiyuki Yoshida, Hiroshi Eisaki, Kenji Kawashima, Hiraku Ogino. 2024-03-29. Synthesis of $c$-axis textured CaKFe$_4$As$_4$ superconducting bulk via spark plasma texturing technique. https://doi.org/10.1016/j.jallcom.2023.171093

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