High-throughput screening of strong electron-phonon couplings in ternary metal diborides

Renhai Wang; Yang Sun; Feng Zhang; Feng Zheng; Yimei Fang; Shunqing Wu; Huafeng Dong; Cai-Zhuang Wang; Vladimir Antropov; Kai-Ming Ho

arXiv · 2207.10134

High-throughput screening of strong electron-phonon couplings in ternary metal diborides

Renhai Wang·Yang Sun·Feng Zhang·Feng Zheng·Yimei Fang·Shunqing Wu·Huafeng Dong·Cai-Zhuang Wang·Vladimir Antropov·Kai-Ming Ho

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Abstract

We perform a high-throughput screening on phonon-mediated superconductivity in ternary metal diboride structure with alkali, alkaline earth, and transition metals. We find 17 ground states and 78 low-energy metastable phases. From fast calculations of zone-center electron-phonon coupling, 43 compounds are revealed to show electron-phonon coupling strength higher than that of MgB2. An anti-correlation between energetic stability and electron-phonon coupling strength is identified. We suggest two phases, i.e., Li3ZrB8 and Ca3YB8, to be synthesized, which show reasonable energetic stability and superconducting critical temperature.

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Renhai Wang, Yang Sun, Feng Zhang, Feng Zheng, Yimei Fang, Shunqing Wu, Huafeng Dong, Cai-Zhuang Wang, Vladimir Antropov, Kai-Ming Ho. 2022-07-20. High-throughput screening of strong electron-phonon couplings in ternary metal diborides. https://arxiv.org/abs/2207.10134

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