Research On Spin-related Transportation In Multilayers Under Different External Field

Multilayers with ferromagnetism/non-ferromagnetism interfaces always have important impact on spintronics,as it could provide special physical properties like spatial symmetry breaking and perpendicular anisotropy,which could assist the current switching of magnetic moment and high-density storage.Therefore the research on transport properties of multilayers,especially its response to external field and the related mechanism,could enlighten the following effort on developing new spintronic devices.In this area,we mainly demonstrate two works :First,the Pt/Co multilayers are deposited on the silicon substrate and fabricated into patterns that are used to measure the anomalous Hall angle and anomalous Nernst coefficient.The interfacial-number dependence of these two coefficients and their correlation is discussed.The positive monotonic correlation between these two coefficients is acquired based on the linear response theory.Compared with the experiment result,this correlation that both effects are enhanced by the incensement of the spin-orbit coupling strength is confirmed.Second,ferromagnetism/insulator barrier/heavy metal(FM/I/HM)multilayer were deposited and annealed to introduce in-plane easy-axis.Fabrication process make them into tunnel junctions with one top electrode and three bottom electrodes.Loading AC on the junction,non-equilibrium spins were injected into the HM layer and could be detected by the inverse spin Hall effect between two bottom electrodes.The junction resistance with 2nd harmonic measurement under perpendicular magnetic field was performed and the spin relaxation time of Platinum and Tantalum was acquired by fitting the magnetic dependence of junction resistance.