Magneto-transport in half metallic CrO₂ nanowires with spin texture

Magneto-transport in ferromagnetic metals (FM) is influenced by spin textures. In this work, we study the magneto-transport of spin textures in epitaxial half-metallic CrO₂ nanowires. We quantitatively define the spatial non-uniformity of spin textures as spin curvature. We design geometric notches along the edges of the 300nm-width wires to introduce the spin curvature. The magnitude of the spin curvature is controlled via both the depth of notches and the magnetic fields. Through micromagnetic simulations and magneto-transport measurements, we uncover an empirical relation between the spin curvature and the magnetoresistance. This provides a quantitative method to predict the magneto-transport behavior of any spin texture. The thermal effect is studied from 10K and 250K. Results show that the thermal magnons worsen the spin asymmetry and suppresses the spin curvature induced resistivity at temperatures much lower than the ferromagnetic ordering temperature T_c.