Magneto-optical signatures of plateau states in the kagome spin-ice HoAgGe
The study investigated unusual transport and optical properties in HoAgGe, a rare-earth magnet with complex magnetic ordering known as kagome spin ice. Researchers used magnetoreflectance spectroscopy and *ab initio* calculations to show that the optical conductivity is unusually high for light polarized perpendicular to the kagome plane. This is linked to flat bands formed by Ho 4f electrons near the Fermi level, suggesting these heavy-electron states control the material's electronic and optical behavior.