Charting the Landscape of Bardeen-Cooper-Schrieffer Superconductors in Experimentally Known Compounds

We perform a high-throughput computational search for novel phonon-mediated superconductors, starting from the Materials Cloud three-dimensional structure database of experimentally known inorganic stoichiometric compounds. We first compute the Allen-Dynes critical temperature (<a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:msubsup><a:mi>T</a:mi><a:mi>c</a:mi><a:mi>AD</a:mi></a:msubsup></a:math>) for <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"><c:mn>4533</c:mn></c:math> nonmagnetic metals using a direct and progressively finer sampling of the electron-phonon couplings. For the candidates with the largest <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" display="inline"><e:msubsup><e:mi>T</e:mi><e:mi>c</e:mi><e:mi>AD</e:mi></e:msubsup></e:math> value, we use automated Wannierizations and electron-phonon interpolations to obtain a high-quality data set for the most promising <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" display="inline"><g:mn>250</g:mn></g:math> dynamically stable structures, for which we calculate spectral functions, superconducting band gaps, and isotropic Migdal-Eliashberg critical temperatures. For <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" display="inline"><i:mn>140</i:mn></i:math> of these, we also provide anisotropic Migdal-Eliashberg superconducting gaps and critical temperatures. The approach is remarkably successful in finding known superconductors and we find <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" display="inline"><k:mn>24</k:mn></k:math> unknown ones with a predicted anisotropic <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" display="inline"><m:msub><m:mi>T</m:mi><m:mi>c</m:mi></m:msub></m:math> value above 10 K. Among them, we identify a possible double-gap superconductor (<o:math xmlns:o="http://www.w3.org/1998/Math/MathML" display="inline"><o:mi>p</o:mi></o:math>-doped <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" display="inline"><q:mrow><q:mi>Ba</q:mi><q:mi mathvariant="normal">B</q:mi></q:mrow></q:math><t:math xmlns:t="http://www.w3.org/1998/Math/MathML" display="inline"><t:msub><t:mi/><t:mn>2</t:mn></t:msub></t:math>), a nonmagnetic half-Heusler <v:math xmlns:v="http://www.w3.org/1998/Math/MathML" display="inline"><v:mrow><v:mi>Zr</v:mi><v:mi>Ru</v:mi><v:mi>Sb</v:mi></v:mrow></v:math>, and the perovskite <x:math xmlns:x="http://www.w3.org/1998/Math/MathML" display="inline"><x:mrow><x:mi>Ta</x:mi><x:mi>Ru</x:mi></x:mrow></x:math><z:math xmlns:z="http://www.w3.org/1998/Math/MathML" display="inline"><z:msub><z:mi/><z:mn>3</z:mn></z:msub></z:math><bb:math xmlns:bb="http://www.w3.org/1998/Math/MathML" display="inline"><bb:mrow><bb:mrow><bb:mi mathvariant="normal">C</bb:mi></bb:mrow></bb:mrow></bb:math>, all exhibiting significant <eb:math xmlns:eb="http://www.w3.org/1998/Math/MathML" display="inline"><eb:msub><eb:mi>T</eb:mi><eb:mi>c</eb:mi></eb:msub></eb:math> values. Finally, we introduce a sensitivity analysis to estimate the robustness of the predictions.