In this study,current-induced partial magnetization-based switching was realized through the spin–orbit torque(SOT)in single-layer L1_(0) FePt with a perpendicular anisotropy(K_(u⊥))of 1.19×10^(7) erg·cm^(...In this study,current-induced partial magnetization-based switching was realized through the spin–orbit torque(SOT)in single-layer L1_(0) FePt with a perpendicular anisotropy(K_(u⊥))of 1.19×10^(7) erg·cm^(-3)(1 erg·cm^(-3)=0.1 J·m^(-3)),and its corresponding SOT efficiency(βDL)was 8×10^(-6) Oe·(A·cm^(-2))^(-1)(1 Oe=79.57747 A·m^(-1)),which is several times higher than that of the traditional Ta/CoFeB/MgO structure reported in past work.The SOT in the FePt films originated from the structural inversion asymmetry in the FePt films since the dislocations and defects were inhomogeneously distributed within the samples.Furthermore,the FePt grown on MgO with a granular structure had a larger effective SOT field and effi-ciency than that grown on SrTiO_(3)(STO)with a continuous structure.The SOT efficiency was found to be considerably dependent on not only the sputtering temperature-induced chemical ordering but also the lattice mismatch-induced evolution of the microstructure.Our findings can provide a useful means of efficiently electrically controlling a magnetic bit that is highly thermally stable via SOT.展开更多
Ti-Ni composite sub-micron powders with different compositions were prepared by vacuum melting and atomization technology.These powders,after being mixed with a solution of phenolic resin and alcohol,were applied on t...Ti-Ni composite sub-micron powders with different compositions were prepared by vacuum melting and atomization technology.These powders,after being mixed with a solution of phenolic resin and alcohol,were applied on the mold cavity wall,by which a casting-infiltration layer was introduced on the surface of ZG45 steel via reactions between the powders and molten steel under the heat released by solidification.The effects of the powders’composition and pouring temperature on the corrosion resistance of the casting-infiltration layer were studied.An optimal casting-infiltration layer with a thickness of~7 mm was obtained by infiltrating the Ti-Ni composite powders containing 35wt.%Ti to ZG45 steel pouring at 1,650℃.The casting-infiltration layer has a good metallurgic bonding with the matrix,and is mainly composed of Fe_(2)Ti phase and continuousγ-(Fe,Ni)solid solution.In the corrosive H_(2)SO_(4) solution,the corrosion potential of the casting-infiltration layer is lower than the matrix,tending to form a passivation film,which lowers the dissolution rate especially when the potential rises to 0.50 V.After dipping in the 10wt.%NaCl solution for 480 h,a lot of corrosion holes appear in the ZG45 steel matrix,while there are no obvious traces of corrosion on the casting-infiltration layer.展开更多
基金supported by National Key Research and Development Program of China (2020AAA0109005)the National Natural Science Foundation of China (61674062, 51501168, 41574175, and 41204083)+3 种基金the Fundamental Research Funds for the Central Universities of the China University of Geosciences (Wuhan) (CUG150632 and CUGL160414)the Fundamental Research Funds for National Universities of the China University of Geosciences (Wuhan)the Interdisciplinary program of Wuhan National High Magnetic Field Center (WHMFC202119)Huazhong University of Science and Technology, and Fund from Shenzhen Virtual University Park (2021Szvup091)
文摘In this study,current-induced partial magnetization-based switching was realized through the spin–orbit torque(SOT)in single-layer L1_(0) FePt with a perpendicular anisotropy(K_(u⊥))of 1.19×10^(7) erg·cm^(-3)(1 erg·cm^(-3)=0.1 J·m^(-3)),and its corresponding SOT efficiency(βDL)was 8×10^(-6) Oe·(A·cm^(-2))^(-1)(1 Oe=79.57747 A·m^(-1)),which is several times higher than that of the traditional Ta/CoFeB/MgO structure reported in past work.The SOT in the FePt films originated from the structural inversion asymmetry in the FePt films since the dislocations and defects were inhomogeneously distributed within the samples.Furthermore,the FePt grown on MgO with a granular structure had a larger effective SOT field and effi-ciency than that grown on SrTiO_(3)(STO)with a continuous structure.The SOT efficiency was found to be considerably dependent on not only the sputtering temperature-induced chemical ordering but also the lattice mismatch-induced evolution of the microstructure.Our findings can provide a useful means of efficiently electrically controlling a magnetic bit that is highly thermally stable via SOT.
基金financially supported by the National Key R&D Program of China(Grant No.2016YFB0300603)。
文摘Ti-Ni composite sub-micron powders with different compositions were prepared by vacuum melting and atomization technology.These powders,after being mixed with a solution of phenolic resin and alcohol,were applied on the mold cavity wall,by which a casting-infiltration layer was introduced on the surface of ZG45 steel via reactions between the powders and molten steel under the heat released by solidification.The effects of the powders’composition and pouring temperature on the corrosion resistance of the casting-infiltration layer were studied.An optimal casting-infiltration layer with a thickness of~7 mm was obtained by infiltrating the Ti-Ni composite powders containing 35wt.%Ti to ZG45 steel pouring at 1,650℃.The casting-infiltration layer has a good metallurgic bonding with the matrix,and is mainly composed of Fe_(2)Ti phase and continuousγ-(Fe,Ni)solid solution.In the corrosive H_(2)SO_(4) solution,the corrosion potential of the casting-infiltration layer is lower than the matrix,tending to form a passivation film,which lowers the dissolution rate especially when the potential rises to 0.50 V.After dipping in the 10wt.%NaCl solution for 480 h,a lot of corrosion holes appear in the ZG45 steel matrix,while there are no obvious traces of corrosion on the casting-infiltration layer.
