A systematic investigation of spin injection behavior in Au/FM(FM=Fe and Ni)multilayers is performed using the superdiffusive spin transport theory.By exciting the nonmagnetic layer,the laser-induced hot electrons may...A systematic investigation of spin injection behavior in Au/FM(FM=Fe and Ni)multilayers is performed using the superdiffusive spin transport theory.By exciting the nonmagnetic layer,the laser-induced hot electrons may transfer spin angular momentum into the adjacent ferromagnetic(FM)metals resulting in ultrafast demagnetization or enhancement.We find that these experimental phenomena sensitively depend on the particular interface reflectivity of hot electrons and may reconcile the different observations in the experiment.Stimulated by the ultrafast spin currents carried by the hot electrons,we propose the multilayer structures to generate highly spin-polarized currents for the development of future ultrafast spintronics devices.The spin polarization of the electric currents carried by the hot electrons can be significantly enhanced by the joint effects of bulk and interfacial spin filtering.Meanwhile,the intensity of the generated spin current can be optimized by varying the number of repeated stacking units and the thickness of each metallic layer.展开更多
基金Shanxi Normal University was supported by the National Key Research and Development Program of China(Grant No.2022YFB3505301)the National Natural Science Foundation of China(Grant No.12174237)+2 种基金China Postdoctoral Science Foundation(Grant No.2023M732150)the Basic Research Plan of Shanxi Province(Grant Nos.202203021212393,and 202203021222219)the financial support by the National Natural Science Foundation of China(Grant No.12174028)。
文摘A systematic investigation of spin injection behavior in Au/FM(FM=Fe and Ni)multilayers is performed using the superdiffusive spin transport theory.By exciting the nonmagnetic layer,the laser-induced hot electrons may transfer spin angular momentum into the adjacent ferromagnetic(FM)metals resulting in ultrafast demagnetization or enhancement.We find that these experimental phenomena sensitively depend on the particular interface reflectivity of hot electrons and may reconcile the different observations in the experiment.Stimulated by the ultrafast spin currents carried by the hot electrons,we propose the multilayer structures to generate highly spin-polarized currents for the development of future ultrafast spintronics devices.The spin polarization of the electric currents carried by the hot electrons can be significantly enhanced by the joint effects of bulk and interfacial spin filtering.Meanwhile,the intensity of the generated spin current can be optimized by varying the number of repeated stacking units and the thickness of each metallic layer.