The magnetization switching plays an essential role in spintronic devices.In this study,a Pd（3 nm）/Co（0.14–1.68 nm）/Pd（5 nm） wedge film is deposited on an Mg O（111） substrate by molecular beam epitaxy.We inve...The magnetization switching plays an essential role in spintronic devices.In this study,a Pd（3 nm）/Co（0.14–1.68 nm）/Pd（5 nm） wedge film is deposited on an Mg O（111） substrate by molecular beam epitaxy.We investigate the polar magneto-optical Kerr effect（MOKE） and carry out the first-order reversal curve（FORC） measurements.For the wedge system,it is observed that the Co thickness could drive the spin reorientation transition（SRT） from out-of-plane to in-plane.Meanwhile,we find the different types of magnetization switchings in the continuous SRT process,which can originate from the formation of different magnetic compositions.Our work provides the possibility of tuning the interfacial effect,and paves the way to analyzing magnetization switching.展开更多
The full-potential linearized augmented plane wave plus local orbital method is utilized for exploring the electronic,magnetic,and magneto-optical properties of the NiX_(2)(X=Cl,Br,and I)single layer.The first-princip...The full-potential linearized augmented plane wave plus local orbital method is utilized for exploring the electronic,magnetic,and magneto-optical properties of the NiX_(2)(X=Cl,Br,and I)single layer.The first-principles calculation demonstrates that these compounds are ferromagnetic indirect semiconductors,and the energy band gaps of NiX_(2)for X=Cl,Br,and I are 3.888,3.134,and 2.157 eV,respectively.The magnetic moments of Ni atoms in NiX_(2)monolayer are 1.656,1.588,1.449μB,and their magneto-crystalline anisotropy energies are 0.167,0.029,0.090 meV,respectively.Based on the macro-linear response theory,we systematically studied the influences of the external magnetic field and out-of-plane strain on the magneto-optical Kerr effect(MOKE)spectrum of the NiX_(2)single layer.It is found that,when the external magnetic field is perpendicular to the sample plane,the value of the Kerr rotation angle reaches the maximum,and the single-layer NiI_(2)material has a Kerr rotation angle of 1.89°at the photon energy of 1.986 eV.Besides,the Kerr rotation spectrum of NiCl_(2)and NiBr_(2)monolayers redshift as the out-of-plane strain increases,while NiI_(2)monolayer blueshifts.Accurate computation of the MOKE spectrum of NiX_(2)materials provides an opportunity for applications of 2D magnetic material ranging from sensing to data storing.展开更多
A series of trilayers of sputtered Fe/Si/Fe were grown to study the interface characteristics and magnetic coupling between ferromagnetic Fe layers (30 ? thick) for Si spacer thickness (tSi) ranging from 15 ? to 40 ?....A series of trilayers of sputtered Fe/Si/Fe were grown to study the interface characteristics and magnetic coupling between ferromagnetic Fe layers (30 ? thick) for Si spacer thickness (tSi) ranging from 15 ? to 40 ?. Grazing incidence x-ray diffraction, AFM, resistivity and x-ray photoelectron spectroscopy (XPS) meas-urements show substantial intermixing between the layers during deposition which results in trilayers of complicated structures for different sub-layer thicknesses. A systematic variation in silicide concentration across the interface is observed by XPS measurements. The Fe layers in the trilayers were observed to con-sist of Fe layers doped with Si, ferromagnetic Fe-Si silicide layers and nonmagnetic Fe-Si silicide interface layer, while the Si spacer was found to be Fe-Si compound layers with an additional amorphous Si (α-Si) sublayer for tSi≥ 30 ?. A strong anti-ferromagnetic (AF) coupling was observed in trilayers with iron silicide spacers, which disappeared if α-Si layers present in the spacers. The observed magnetization behaviour in each case is interpreted in terms of changes in interfacial structural and electronic properties due to variation in film thickness.展开更多
基金Project supported by the National Basic Research Program of China(Grant Nos.2015CB921403 and 2016YFA0300701)the National Natural Science Foundation of China(Grant Nos.51427801,11374350,and 51671212)
文摘The magnetization switching plays an essential role in spintronic devices.In this study,a Pd（3 nm）/Co（0.14–1.68 nm）/Pd（5 nm） wedge film is deposited on an Mg O（111） substrate by molecular beam epitaxy.We investigate the polar magneto-optical Kerr effect（MOKE） and carry out the first-order reversal curve（FORC） measurements.For the wedge system,it is observed that the Co thickness could drive the spin reorientation transition（SRT） from out-of-plane to in-plane.Meanwhile,we find the different types of magnetization switchings in the continuous SRT process,which can originate from the formation of different magnetic compositions.Our work provides the possibility of tuning the interfacial effect,and paves the way to analyzing magnetization switching.
文摘The full-potential linearized augmented plane wave plus local orbital method is utilized for exploring the electronic,magnetic,and magneto-optical properties of the NiX_(2)(X=Cl,Br,and I)single layer.The first-principles calculation demonstrates that these compounds are ferromagnetic indirect semiconductors,and the energy band gaps of NiX_(2)for X=Cl,Br,and I are 3.888,3.134,and 2.157 eV,respectively.The magnetic moments of Ni atoms in NiX_(2)monolayer are 1.656,1.588,1.449μB,and their magneto-crystalline anisotropy energies are 0.167,0.029,0.090 meV,respectively.Based on the macro-linear response theory,we systematically studied the influences of the external magnetic field and out-of-plane strain on the magneto-optical Kerr effect(MOKE)spectrum of the NiX_(2)single layer.It is found that,when the external magnetic field is perpendicular to the sample plane,the value of the Kerr rotation angle reaches the maximum,and the single-layer NiI_(2)material has a Kerr rotation angle of 1.89°at the photon energy of 1.986 eV.Besides,the Kerr rotation spectrum of NiCl_(2)and NiBr_(2)monolayers redshift as the out-of-plane strain increases,while NiI_(2)monolayer blueshifts.Accurate computation of the MOKE spectrum of NiX_(2)materials provides an opportunity for applications of 2D magnetic material ranging from sensing to data storing.
文摘A series of trilayers of sputtered Fe/Si/Fe were grown to study the interface characteristics and magnetic coupling between ferromagnetic Fe layers (30 ? thick) for Si spacer thickness (tSi) ranging from 15 ? to 40 ?. Grazing incidence x-ray diffraction, AFM, resistivity and x-ray photoelectron spectroscopy (XPS) meas-urements show substantial intermixing between the layers during deposition which results in trilayers of complicated structures for different sub-layer thicknesses. A systematic variation in silicide concentration across the interface is observed by XPS measurements. The Fe layers in the trilayers were observed to con-sist of Fe layers doped with Si, ferromagnetic Fe-Si silicide layers and nonmagnetic Fe-Si silicide interface layer, while the Si spacer was found to be Fe-Si compound layers with an additional amorphous Si (α-Si) sublayer for tSi≥ 30 ?. A strong anti-ferromagnetic (AF) coupling was observed in trilayers with iron silicide spacers, which disappeared if α-Si layers present in the spacers. The observed magnetization behaviour in each case is interpreted in terms of changes in interfacial structural and electronic properties due to variation in film thickness.
