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arXiv · 2406.14524

High-Tc superconductor candidates proposed by machine learning

Abstract

We cast the relation between the chemical composition of a solid-state material and its superconducting critical temperature (Tc) as a statistical learning problem with reduced complexity. Training of query-aware similarity-based ridge regression models on experimental SuperCon data achieve average Tc prediction errors of ~5 K for unseen out-of-sample materials. Two models were trained with one excluding high pressure data in training ("ambient" model) and a second also including high pressure data ("implicit" model). Subsequent utilization of the approach to scan ~153k materials in the Materials Project enables the ranking of candidates by Tc while accounting for thermodynamic stability and small band gap. The ambient model is used to predict stable top three high-Tc candidate materials that include those with large band gaps of LiCuF4 (316 K), Ag2H12S(NO)4 (316 K), and Na2H6PtO6 (315 K). Filtering these candidates for those with small band gaps correspondingly yields LiCuF4 (316 K), Cu2P2O7 (311 K), and Cu3P2H2O9 (307 K).

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Siwoo Lee, Jason Hattrick-Simpers, Young-June Kim, O. Anatole von Lilienfeld. 2024-11-07. High-Tc superconductor candidates proposed by machine learning. https://arxiv.org/abs/2406.14524

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