Anisotropy, frustration, and saddle point in the twisted kagome antiferromagnet ErPdPb

The kagome lattice has long attracted interest because its geometric frustration can give rise to unusual quantum states. When this lattice is distorted into a twisted or buckled arrangement, the resulting magnetic and electronic behavior becomes even richer. In this work, the authors synthesize and characterize single crystals of ErPdPb, a twisted kagome antiferromagnet in which the Er atoms form a frustrated magnetic network within the noncentrosymmetric ZrNiAl-type structure. Below 2.7 K, ErPdPb enters a strongly anisotropic magnetic state marked by fractional magnetization plateaus, competing exchange interactions, and pronounced directional dependence in its electronic properties. First-principles calculations in the field-polarized ferromagnetic state further reveal a spin-split saddle point close to the Fermi level and a quasi-one-dimensional Fermi surface. Together, these findings identify ErPdPb as a promising platform for investigating the interplay of magnetic frustration, electronic anisotropy, and topological band structure.