The Nature and Origin of Spin Moiré Superlattices in the Europium Triangle Lattice Material EuAg4Sb2

Recently, lanthanide intermetallics have been the subject of intense research due to the discovery of skyrmions in materials such as centrosymmetric Gd-containing Gd2PdSi3, GdRu2Si2, Gd3Ru4Al12, and Eu-containing EuAl4 and EuNiGe3. In addition to hosting skyrmion phases, a hallmark of this class of materials is the appearance of numerous additional magnetic phases in close proximity, highlighting a nuanced energy landscape and thus motivating detailed studies to understand the underlying interactions. EuAg4Sb2 is an electronically clean, quasi-2D europium triangle lattice compound in this family with ballistic-limit coupling between the electronic and magnetic degrees of freedom, recently shown to yield a coherent renormalization of the electronic properties of the material. In this talk, I will discuss our progress using neutron scattering to understand the variety of phases hosted in one material. Our analysis hints at the connection between the rich spin textures in this material, the electronic structure, and frustration—revealing new insights into design principles for nano-scale spin texture materials.