Topological multipolar spin textures*

Strongly correlated quantum materials with partially filled d or f electron shells often exhibit unconventional symmetry-broken higher-order multipolar phases. These phases are commonly referred to as "hidden orders" because they are elusive to conventional magnetic probes like neutron scattering and magnetic resonance. By virtue of the interplay between spin-orbit coupling and crystal electric field splitting, the low-energy physics of these strongly correlated materials can be effectively captured by anisotropic pseudo-spin models of multipolar moments. A well-established fact is that the anisotropies in the dipolar spin models play a pivotal role in stabilizing topological dipolar spin textures, such as skyrmions. This study introduces model systems to stabilize topological multipolar spin textures, offering comprehensive phase diagrams to aid experimental pursuits of these exotic phases. Furthermore, the multipolar nature of these materials introduces anisotropy in the Kondo coupling between spin textures and conduction electrons in the f electron materials. The topological multipolar spin textures can produce an emergent anomalous Hall response, which may serve as a valuable tool for unraveling the hidden orders in these strongly correlated materials.