Zr₃Mn₃Sn₄Ga: A new hetero-kagome bilayer antiferromagnet

We report the magnetic and electrical transport properties of single-crystalline Zr₃Mn₃Sn₄Ga, featuring two distinct kagome lattices: a non-magnetic breathing Zr₃Sn₄ lattice and a magnetic intact Mn₃Ga lattice. The material undergoes an antiferromagnetic phase transition at T_N = 87 K, with neutron diffraction confirming commensurate ordering characterized by k = (1/3,1/3,0). Transport measurements show metallic behavior, a resistivity anomaly near T_N​, and 12 % magnetoresistance at 2 K under 9 T Deviations from the conventional second-order power law, along with negative magnetoresistance and nonlinear Hall slope variations near T_N​, suggest strong magneto-electronic coupling. Resonant photoemission spectroscopy identifies Zr 4d and Mn 3d orbitals as dominant contributors to the valence band, linking the material's unique electronic properties to its kagome layers. Zr₃Mn₃Sn₄Ga offers a valuable platform to study interactions between magnetism and topological electronic bands in hetero-kagome systems using the co-existence of magnetic and non-magnetic kagome layers and its tunable electronic structure.