Anomalous magnetoresistance and Hall effect in amorphous Pt/TbFeCo thin films

Abstract

Among the magnetic materials in technological usage, amorphous rare-earth transition metal (RE-TM) alloys are of great interest due to their adjustable magnetic properties and favorable perpendicular magnetic anisotropic (PMA) advantages. In this study, the properties of Tb(25)Fe(6)1Co(14) system with 2, 5, and 10 nm Pt underlayers have been systematically explored by X-ray diffraction (XRD), transmission electron microscopy (TEM), temperature and magnetic field dependence of Hall resistivity, magnetoresistivity, and magneto-optic Kerr Effect (MOKE) measurements. According to the results, whole thin films are amorphous in nature and display an out-of-plane magnetic anisotropy without annealing. Increasing the Pt underlayer thickness helps the TbFeCo layer to reach significantly enhanced perpendicular magnetic anisotropic values and visualize the appearance of anomalous magnetoresistance in the Hall effect measurements. The thin films with 5 and 10 nm Pt underlayer has a ratio of remanence magnetization/saturation magnetization (MR/MS) of around 1, which is the out of plane direction of MOKE signal. Besides, the present study also includes some pieces of evidence that might be related to the Berry phase trend.