The magneto-optical Kerr effect susceptometry technique is proposed to determine the uniaxial magnetic anisotropy （UMA） constant Ku. The magnetic properties of Cu/Fe/SiO2/Si grown by dc magnetron sputtering were inv...The magneto-optical Kerr effect susceptometry technique is proposed to determine the uniaxial magnetic anisotropy （UMA） constant Ku. The magnetic properties of Cu/Fe/SiO2/Si grown by dc magnetron sputtering were investigated. The in-plane uniaxial magnetic anisotropy was probed by the magneto-optical Kerr effect （MOKE）. The value of UMA, Ku = 2.5 x 103 J/m3, was simulated from the field dependence of ac susceptibility along the hard axis according to the Stoner-Wohlfarth （S-W） model, which is consistent with Ku = 2.7~ 103 J/m3 calculated from the magnetic hysteresis loops. Our results show that the magneto-optical Kerr effect susceptometry can be employed to determine the magnetic anisotropy constant owing to its high sensitivity.展开更多
According to ultraviolet （UV）-vis absorption spectra recorded in the DNA metallization process, DNA-templated Co/Cu binary nanoparticle chains are fabricated by incubating genome DNA of paralichthys olivaceus muscle...According to ultraviolet （UV）-vis absorption spectra recorded in the DNA metallization process, DNA-templated Co/Cu binary nanoparticle chains are fabricated by incubating genome DNA of paralichthys olivaceus muscle in CoCl2 and CuCl2 mixture solution for 20 hours and reducing the complex for 2 hours. Transmission electron microscopy observation indicates that Co and Cu nanoparticles with 20 nm in diameter were randomly dispersed on the DNA template. The superconducting quantum interference device （SQUID） measurements display that the magnetic interaction between cobalt particles is greatly decreased by the copper particle. With increasing copper content, the coercivity of the systems enhance from 9 Oe to 100 Oe （1 Oe=79.5775 A/m）.展开更多
Exchange-spring magnet L1-FePt/（Fe2B＋a-Fe） is fabricated by flash annealing a melt-spun Fe48Pt34B18 foil. A coercivity of 8500 Oe （1Oe = 79.5775 A/m）, squareness （Mr/Ms） of 0.70, saturation magnetization of 10....Exchange-spring magnet L1-FePt/（Fe2B＋a-Fe） is fabricated by flash annealing a melt-spun Fe48Pt34B18 foil. A coercivity of 8500 Oe （1Oe = 79.5775 A/m）, squareness （Mr/Ms） of 0.70, saturation magnetization of 10.2 kGs （1 Gs = 10-4 T） and an effective anisotropy Keg = 2.0 × 10^7 ergs/cm3 are obtained. A two-step magnetization reversal feature is characterized in this paper. An exchange bias phenomenon is also observed in a low saturation field.展开更多
基金Project supported by the National Basic Research Program of China(Grant Nos.2009CB929201,2011CB921801,and 2012CB933102)the National Natural Science Foundation of China(Grant Nos.50931006,11034004,51021061,and 11274033)
文摘The magneto-optical Kerr effect susceptometry technique is proposed to determine the uniaxial magnetic anisotropy （UMA） constant Ku. The magnetic properties of Cu/Fe/SiO2/Si grown by dc magnetron sputtering were investigated. The in-plane uniaxial magnetic anisotropy was probed by the magneto-optical Kerr effect （MOKE）. The value of UMA, Ku = 2.5 x 103 J/m3, was simulated from the field dependence of ac susceptibility along the hard axis according to the Stoner-Wohlfarth （S-W） model, which is consistent with Ku = 2.7~ 103 J/m3 calculated from the magnetic hysteresis loops. Our results show that the magneto-optical Kerr effect susceptometry can be employed to determine the magnetic anisotropy constant owing to its high sensitivity.
基金Project partially supported by the Key Project of the Ministry of Education of China(Grant No.109025)
文摘According to ultraviolet （UV）-vis absorption spectra recorded in the DNA metallization process, DNA-templated Co/Cu binary nanoparticle chains are fabricated by incubating genome DNA of paralichthys olivaceus muscle in CoCl2 and CuCl2 mixture solution for 20 hours and reducing the complex for 2 hours. Transmission electron microscopy observation indicates that Co and Cu nanoparticles with 20 nm in diameter were randomly dispersed on the DNA template. The superconducting quantum interference device （SQUID） measurements display that the magnetic interaction between cobalt particles is greatly decreased by the copper particle. With increasing copper content, the coercivity of the systems enhance from 9 Oe to 100 Oe （1 Oe=79.5775 A/m）.
基金supported by the Foundation for Key Program of Ministry of Education, China (Grant No. 109025)the Fundamental Research Funds for the Central Universities of China (Grant No. 101-105113)
文摘Exchange-spring magnet L1-FePt/（Fe2B＋a-Fe） is fabricated by flash annealing a melt-spun Fe48Pt34B18 foil. A coercivity of 8500 Oe （1Oe = 79.5775 A/m）, squareness （Mr/Ms） of 0.70, saturation magnetization of 10.2 kGs （1 Gs = 10-4 T） and an effective anisotropy Keg = 2.0 × 10^7 ergs/cm3 are obtained. A two-step magnetization reversal feature is characterized in this paper. An exchange bias phenomenon is also observed in a low saturation field.
