Comment on "Trapped flux in a small crystal of CaKFe$_4$As$_4$ at ambient pressure and in a diamond anvil pressure cell" by S. L. Bud'ko et al

J. E. Hirsch; F. Marsiglio

doi:10.1007/s10948-025-06948-1

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arXiv · 2405.17500

Comment on "Trapped flux in a small crystal of CaKFe$_4$As$_4$ at ambient pressure and in a diamond anvil pressure cell" by S. L. Bud'ko et al

J. E. Hirsch·F. Marsiglio

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Abstract

In their paper arXiv:2405.08189, Supercond. Sci. Technol. 37 (2024) 065010 [1], Bud'ko et al. present experimental results for trapped magnetic flux for a tiny sample of a type II superconductor. The paper aims to provide evidence in support of the interpretation that similar measurements performed in samples of hydrogen-rich materials under high pressure by Minkov, Bud'ko and coauthors [2] are conclusive evidence [3] for superconductivity in hydrides under pressure. Here we point out that the new evidence presented by Bud'ko et al. [1] further supports our interpretation [4],[5] that the reported measurements of trapped flux on hydrides under pressure [2] are evidence that the samples are $not$ superconducting.

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J. E. Hirsch, F. Marsiglio. 2024-05-26. Comment on "Trapped flux in a small crystal of CaKFe$_4$As$_4$ at ambient pressure and in a diamond anvil pressure cell" by S. L. Bud'ko et al. https://doi.org/10.1007/s10948-025-06948-1

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