  Kagome metals are as an exciting playground for the explorations of novel
phenomena at the intersection of topology, electron correlations and magnetism.
The family of FeSn-based kagome magnets in particular attracted a lot of
attention for simplicity of the layered crystal structure and tunable
topological electronic band structure. Despite a significant progress in
understanding their bulk properties, surface electronic and magnetic structures
are yet to be fully explored in many of these systems. In this work, we focus
on a prototypical kagome metal FeSn. Using a combination of spin-averaged and
spin-polarized scanning tunneling microscopy, we provide the first atomic-scale
visualization of the layered antiferromagnetic structure at the surface of
FeSn. In contrast to the field-tunable electronic structure of cousin material
Fe3Sn2 that is a ferromagnet, we find that electronic density-of-states of FeSn
is robust to the application of external magnetic field. Interestingly, despite
the field-insensitive electronic band structure, FeSn exhibits bounds states
tied to specific impurities with large effective moments that strongly couple
to the magnetic field. Our experiments provide microscopic insights necessary
for theoretical modeling of FeSn and serve as a spring board for spin-polarized
measurements of topological magnets in general.
