Sign reversal and manipulation of anomalous Hall resistivity in facing-target sputtered Pt/Mn_(4)N bilayers

摘要

The magnetic and electronic transport properties manipulated by spin-orbit torque have been devoted much attention as they show a great promise for future spintronic devices.Here,the spin dependent transport properties of the facing-target sputtered Pt/Mn_(4)N bilayers on MgO(001)substrates have been investigated systematically.The Hall resistivity of Pt/Mn_(4)N bilayers is strongly dependent on temperature,applied current intensity,Mn_(4)N and Pt layer thicknesses.The temperature-dependent sign reversal of anomalous Hall resistivity appears in Pt/Mn_(4)N bilayers,which is dominated by the competition between the magnetic proximity and spin Hall effects.Besides,the magnitude of anomalous Hall resistivity can be manipulated by applied current density.The critical and saturation currents are related to Mn_(4)N and Pt layer thicknesses.Furthermore,a Dzyaloshinskii-Moriya interaction coefficient(D)of 5.63 mJ·m^(-2)is calculated in Pt/Mn_(4)N/MgO systems.The details of the anomalous Hall effects in Pt/Mn_(4)N bilayers are helpful to understand the interfacial effects between heavy metals and ferrimagnets.