Unconventional flat band (FB) superconductivity, as observed in van der Waals
heterostructures, could open promising avenues towards high-Tc​ materials.
Indeed, in FBs, pairings and superfluid weight scale linearly with the
interaction parameter, such an unusual behaviour justifies strategies to
promote FB engineering. Bipartite lattices (BLs) which naturally host FBs could
be particularly interesting candidates. By revealing a hidden symmetry of the
quasi-particle eigenstates, we demonstrate that pairings and superfluid weight
obey universal relations in BLs. Remarkably, these general properties are
insensitive to disorder as long as the bipartite character is protected.Comment: 5 figure