Exploring the cascade of metamagnetic transitions in centrosymmetric magnet NdRh₂Ge₂

Centrosymmetric magnets in the ThCr₂Si₂ structure have garnered a reputation for hosting a wide range of properties, including ferromagnetism, antiferromagnetism, and, more recently, skyrmion-lattices in GdRu₂Si₂ and EuAl₄. The existence of various field-induced magnetic structures, as well as spin textures, make the compounds in this family ideal candidates for studying the interplay of multi-Q order and topology. In this talk, we reveal the field-induced magnetic order in NdRh₂Ge₂ with magnetization, heat capacity, electronic transport, and single-crystal neutron diffraction measurements. NdRh₂Ge₂ shares a strikingly similar magnetic phase diagram with the Gd-based centrosymmetric skyrmion magnet. However, unlike the Heisenberg moments of Gd, Nd has an Ising-like single-ion anisotropy with significantly smaller moments. We show that the phase diagram of NdRh₂Ge₂ contains a cascade of metamagnetic transitions, including commensurate and incommensurate states. These results underscore the complex relationship between single-ion anisotropy, electronic structure, and magnetic order.