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arXiv · 2409.03809

Competition between the modification of intrinsic superconducting properties and the pinning landscape under external pressure in CaKFe$_4$As$_4$ single crystals

Shuyuan Huyan·Nestor Haberkorn·Mingyu Xu·Paul C. Canfield·Sergey L. Bud'ko
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Abstract

Measurements of low field magnetization, trapped flux magnetization and 5 K flux creep in single crystal of CaKFe$_4$As$_4$ under pressure up to 7.5 GPa in a diamond pressure cell are presented. The observed evolution of the temperature dependence of the self-field critical current and slowing down of the base temperature flux creep rate are explained within the two sources of pinning hypothesis involving presence of CaKFe$_4$As$_4$ intergrowths suggested in the literature. Above the half collapsed tetragonal structural transition under pressure, where superconductivity is non-bulk or absent, critically diminished or no diamagnetism and flux trapped magnetization were observed.

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Shuyuan Huyan, Nestor Haberkorn, Mingyu Xu, Paul C. Canfield, Sergey L. Bud'ko. 2024-09-05. Competition between the modification of intrinsic superconducting properties and the pinning landscape under external pressure in CaKFe$_4$As$_4$ single crystals. https://arxiv.org/abs/2409.03809

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