Controlling the phase of light in magnetoplasmonic structures is receiving increasing attention because of its already shown capability in ultrasensitive and label-free molecular-level detection.Magneto-optical Kerr r...Controlling the phase of light in magnetoplasmonic structures is receiving increasing attention because of its already shown capability in ultrasensitive and label-free molecular-level detection.Magneto-optical Kerr reversal has been achieved and well explained in nanodisks by using the phase of localized plasmons.In this paper,we report that the Kerr reversal can also be produced by surface plasmon polaritons independently.We experimentally confirm this in Co and Ag/Co/Ag metal nanogratings,and can give a qualitative explanation that it is the charge accumulation at the interface between the grating surface and air that acts as the electromagnetic restoring force to contribute necessary additional phase for Kerr reversal.Our finding can enrich the means of designing and fabricating magneto-optical-based biochemical sensors.展开更多
The low-temperature magnetic order behaviors of perovskite oxide CaCu_(3)Ti_(4)O_(12)(CCTO)ceramics prepared by different methods are discussed.X-ray diffraction,scanning electron microscope,x-ray photoelectron spectr...The low-temperature magnetic order behaviors of perovskite oxide CaCu_(3)Ti_(4)O_(12)(CCTO)ceramics prepared by different methods are discussed.X-ray diffraction,scanning electron microscope,x-ray photoelectron spectroscopy,and direct current(DC)magnetization are used to characterize the structures,microscopic morphologies,valence states,and magnetic properties of the samples.The results show that the magnetic behaviors of CCTO ceramics are very sensitive to the preparation process.The quenched CCTO ceramic and CCTO powders grown in a molten salt crystal,which contain much more oxygen vacancies and Ti^(3+),show the coexistence of weak ferromagnetic order and antiferromagnetic order below the Neel temperature.It suggests that the bound magnetopolaron formed by oxygen vacancies and Ti^(3+)ion composite defects are responsible for the weak ferromagnetic order at low temperature.展开更多
The effects of magnetic field annealing on the properties of Fe48Co52 alloy nanowire arrays with various interwire distances (Di=30-60 nm) and wire diameters (Dw=22-46 nm) were investigated in detail. It was found...The effects of magnetic field annealing on the properties of Fe48Co52 alloy nanowire arrays with various interwire distances (Di=30-60 nm) and wire diameters (Dw=22-46 nm) were investigated in detail. It was found that the array's best annealing temperature and crys- talline structure did not show any apparent dependence on the treatment of applying a 3 kOe magnetic field along the wire during the annealing process. For arrays with small Dw or with large Di, the treatment of magnetic field annealing also had no obvious influence on their magnetic performances. However, such a magnetic field annealing constrained the shift of the easy magnetization direction and improved the coercivity and the squareness obviously for arrays with large Dw or with small Di. The difference in the intensity of the effective anisotropic field within the arrays was believed to be responsible for this different variation of the array's magnetic properties after magnetic field annealing.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11374146)the China Postdoctoral Science Foundation(Grant No.2018M632278)the Jiangsu Provincial Planned Projects for Postdoctoral Research Funds,China(Grant No.1701092C)
文摘Controlling the phase of light in magnetoplasmonic structures is receiving increasing attention because of its already shown capability in ultrasensitive and label-free molecular-level detection.Magneto-optical Kerr reversal has been achieved and well explained in nanodisks by using the phase of localized plasmons.In this paper,we report that the Kerr reversal can also be produced by surface plasmon polaritons independently.We experimentally confirm this in Co and Ag/Co/Ag metal nanogratings,and can give a qualitative explanation that it is the charge accumulation at the interface between the grating surface and air that acts as the electromagnetic restoring force to contribute necessary additional phase for Kerr reversal.Our finding can enrich the means of designing and fabricating magneto-optical-based biochemical sensors.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11504227 and 51971128)the Program of Shanghai Academic/Technology Research Leader,China(Grant No.20XD1401800)the Project of the Science and Technology Commission of Shanghai Municipality,China(Grant No.19020501000).
文摘The low-temperature magnetic order behaviors of perovskite oxide CaCu_(3)Ti_(4)O_(12)(CCTO)ceramics prepared by different methods are discussed.X-ray diffraction,scanning electron microscope,x-ray photoelectron spectroscopy,and direct current(DC)magnetization are used to characterize the structures,microscopic morphologies,valence states,and magnetic properties of the samples.The results show that the magnetic behaviors of CCTO ceramics are very sensitive to the preparation process.The quenched CCTO ceramic and CCTO powders grown in a molten salt crystal,which contain much more oxygen vacancies and Ti^(3+),show the coexistence of weak ferromagnetic order and antiferromagnetic order below the Neel temperature.It suggests that the bound magnetopolaron formed by oxygen vacancies and Ti^(3+)ion composite defects are responsible for the weak ferromagnetic order at low temperature.
基金ACKNOWLEDGMENTS This work was supported by the National Nature Science Foundation of China (No.50171033), the National Key Project of Fundamental Research of China (No.2005CB623605), and the Scientific Research Foundation for the Doctor of Hefei University of Technology (No.035032).
文摘The effects of magnetic field annealing on the properties of Fe48Co52 alloy nanowire arrays with various interwire distances (Di=30-60 nm) and wire diameters (Dw=22-46 nm) were investigated in detail. It was found that the array's best annealing temperature and crys- talline structure did not show any apparent dependence on the treatment of applying a 3 kOe magnetic field along the wire during the annealing process. For arrays with small Dw or with large Di, the treatment of magnetic field annealing also had no obvious influence on their magnetic performances. However, such a magnetic field annealing constrained the shift of the easy magnetization direction and improved the coercivity and the squareness obviously for arrays with large Dw or with small Di. The difference in the intensity of the effective anisotropic field within the arrays was believed to be responsible for this different variation of the array's magnetic properties after magnetic field annealing.