← Back to search

Discovery of interpretable Tc descriptors in conventional superconductors guided by symbolic regression

Fang Han Lim, Jinbo Pan, Shixuan Du

DOI 10.1103/4pxk-z8ww · Physical Review Materials

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

Advancement of superconductivity is hindered by complexity of underlying mechanisms. Machine learning models have potential to accelerate materials discovery but face data limitations and interpretability challenges. This study identifies material genes governing conventional superconductivity through systematic two-stage analysis, where atomic descriptors are directly related to their phonon-mediated mechanism, unlike unconventional superconductors where strong electronic correlations that go beyond the Bardeen-Cooper-Schrieffer paradigm dominate in the formation of pairing glue. We first apply the random forest classifier and regressor to 16320 superconductors from NIMS database, screening over 114 MAGPIE and MEREDIG atomic descriptors to identify the 30 most important features. Combining these atomic descriptors with DFT-calculated bulk properties, we then perform SISSO (sure independence screening and sparsifying operator) symbolic regression on 60 carefully selected conventional superconductors. The resulting three-dimensional model [R2=0.778, AFD (average factor difference) =1.173] reveals optimal Tc requires an average of half filled or near half filled d electrons with moderate unfilled orbital heterogeneity. The discovered descriptors integrate d-valence electrons, unfilled orbitals, and electronegativity variations, providing actionable guidelines for materials design.

Similar papers