  Kagome lattices constitute versatile platforms for studying paradigmatic
correlated phases. While molecular self-assembly of kagome structures on
metallic substrates is promising, it is challenging to realize pristine kagome
properties because of hybridization with the bulk degrees of freedom and
modified electron-electron interactions. We suggest that a superconducting
substrate offers an ideal support for a magnetic kagome lattice. Exchange
coupling induces kagome-derived bands at the interface, which are protected
from the bulk by the superconducting energy gap. We realize a magnetic kagome
lattice on a superconductor by depositing Fe-porphin-chloride molecules on
Pb(111) and using temperature-activated de-chlorination and self-assembly. This
allows us to control the formation of smaller kagome precursors and long-range
ordered kagome islands. Using scanning tunneling microscopy and spectroscopy at
1.6 K, we identify Yu-Shiba-Rusinov states inside the superconducting energy
gap and track their hybridization from the precursors to larger islands, where
the kagome lattice induces extended YSR bands. These YSR-derived kagome bands
are protected inside the superconducting energy gap, motivating further studies
to resolve possible spin-liquid or Kondo-lattice-type behavior.
