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arXiv · 2402.12933

Enhancement of the critical current by surface irregularities in Fe-based superconductors

I. F. Llovo·J. Mosqueira·Ding Hu·Huiqian Luo·Shiliang Li
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Abstract

The critical current $I_c$ of single crystals of the iron pnictide superconductor BaFe$_2$(As$_{1-x}$P$_x$)$_2$, has been studied through measurements of magnetic hysteresis cycles. We show that the introduction of surface irregularities in the $\mu$m scale significantly increase $I_c$, primarily near the irreversibility magnetic field $H_{irr}$, where the surface currents are the main contribution to $I_c$. Such an increase is consistent with a theoretical estimate for the maximum non-dissipative current that a rough surface can sustain, based on Mathieu-Simon continuum theory for the vortex state.

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I. F. Llovo, J. Mosqueira, Ding Hu, Huiqian Luo, Shiliang Li. 2024-02-20. Enhancement of the critical current by surface irregularities in Fe-based superconductors. https://doi.org/10.1088/1361-6668%2Fad5114

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