A Strategy Toward Room Temperature Topological Hall Effect via Local Moment Magnetism

Abstract

Topological spin textures in local moment systems hold great promise for technological applications due to their large magnetic moments, strong spin-orbit coupling (SOC), and high tunability. Finding new spin textures that are stable near room temperature is paramount to maximizing their potential for applications. Here, we provide a strategy for realizing topological spin textures at high temperatures by identifying rare earth ($R$) magnets ordering at or near room temperature. We demonstrate the feasibility of this strategy in one of these magnets, hexagonal Gd$_5$Pb$_3$, which orders at $T_C$ = 285 K. The indication for topological spin textures comes from topological Hall effect (THE), which, in Gd$_5$Pb$_3$, occurs between $T$ = 100 - 200 K, an order of magnitude higher temperature than in other reported $R$-based systems. Our results present an opportunity to explore the role of SOC, anisotropic exchange, geometric frustration, and magnetic interactions in stabilizing topological spin textures, and provide a pathway toward realizing them near room temperature in $R$-based magnets.