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arXiv · 2301.09032

Al-Based Few-Hydrogen Metal-Bonded Perovskite High-$T_c$ Superconductor Al$_4$H up to 54 K under Atmospheric Pressure

Yong He·Jing Lu·Xinqiang Wang·Jun-jie Shi
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Abstract

Multi-hydrogen lanthanum hydrides have shown the highest critical temperature $T_c$ at 250-260 K under 170-200 GPa. However, such high pressure is a great challenge for sample preparation and practical application. To address this challenge, we propose a novel design strategy for ambient-pressure high-$T_c$ superconductors by constructing new few-hydrogen metal-bonded perovskite hydrides, such as Al-based superconductor $\rm {Al_4H}$, with better ductility than the well-known multi-hydrogen, cuprate and Fe-based superconductors. Based on the Migdal-Eliashberg theory, we predict that the structurally stable $\rm {Al_4H}$ has a favorable high $T_c$ up to 54 K under atmospheric pressure, similar to SmOFeAs.

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Yong He, Jing Lu, Xinqiang Wang, Jun-jie Shi. 2023-01-22. Al-Based Few-Hydrogen Metal-Bonded Perovskite High-$T_c$ Superconductor Al$_4$H up to 54 K under Atmospheric Pressure. https://doi.org/10.1103/physrevb.108.054515

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