Near-room temperature topological Hall effect at spin reorientations in sputtered NdCo_5-xCu_xthin film

The spin reorientation in rare-earth intermetallics involves distinctive magnetic morphologies commencing with spontaneous skyrmion textures without an external magnetic field. Here, we present the sputtering growth of CaCu5-type NdCo5-xCux thin films on MgO (110) substrates. Our films exhibit two successive spin reorientation transitions between the ab-plane and the c-axis, close to the room temperature, apart from the non-uniaxial behavior below 150 K. The corresponding modulations of magnetocrystalline anisotropy at reorientation temperatures lead to the large topological Hall effect, which can be maintained up to 250 K with a maximum Hall resistivity of 210 nω cm. These results of robust topological signals will provide platforms for realizing room-temperature topological magnetic textures.