Prospects to attain room temperature superconductivity

X. H. Zheng; J. X. Zheng; D. G. Walmsley

doi:10.1016/j.ssc.2019.05.002

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arXiv · 1905.01367

Prospects to attain room temperature superconductivity

X. H. Zheng·J. X. Zheng·D. G. Walmsley

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Abstract

With a generic model for the electron-phonon spectral density, two simple expressions are derived to estimate the transition temperature and gap-to-temperature ratio in conventional superconductors. They entail that on average the numerical value of the phonon exchange factor, $\lambda$, is limited to 2.67, so that room temperature superconductivity may be attained only with a Debye temperature of about 1800 K or higher, in materials that may or may not involve hydrogen. They also show that a Be-Pb alloy may become a superconductor at $\sim$44 K.

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X. H. Zheng, J. X. Zheng, D. G. Walmsley. 2019-05-03. Prospects to attain room temperature superconductivity. https://doi.org/10.1016/j.ssc.2019.05.002

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