A systematic study on the structural, magnetic, and electrical transport properties was performed for the LaMnlxCUxO3 system. A single phase of orthorhornbic perovskite structure was formed for x = 0.05-0.40. A striki...A systematic study on the structural, magnetic, and electrical transport properties was performed for the LaMnlxCUxO3 system. A single phase of orthorhornbic perovskite structure was formed for x = 0.05-0.40. A striking paramagnetic-ferromagnetic transition and a considerable magnetoresistance effect were observed at the ferromagnetic ordering temperature Tc, but no insulator-metal transition induced by Cu-doping was observed. Below Tc, a visible unexpected drop was observed in the ac susceptibility and zero-field-cooled dc magnetization for the dilute doped samples with x≤0.10, which was proven to be associated with domain wall pinning effects by milling the bulk material into single domain particles. It is validated that there is no exchange interaction between Cu and Mn, and double exchange interactions between Mn^3＋ and Mn^4＋ are induced by Cu-doping in the anti-ferromagnetic LaMnO3 matrix, whereas the severe distortion and disorder caused by occupied-dopant prohibits charge carriers from hopping.展开更多
A new thin film pulse transformer for using in ISND and ADSL systems has been designed based on a domain wall pinning model, the parameters of nano-magnetic thin film such as permeability and coercivity can be calcula...A new thin film pulse transformer for using in ISND and ADSL systems has been designed based on a domain wall pinning model, the parameters of nano-magnetic thin film such as permeability and coercivity can be calculated. The main properties of the thin film transformer including the size, parallel inductance, Q value and turn ratio have been simulated and optimized. Simulation results show that the thin film transformer can be fairly operated in a frequency range of 0.001~20 MHz.展开更多
基金supported by Shanghai Rising-Star Program (No. 11QH1401000)the National Natural Science Foundation of China (No. 50932003)+1 种基金the Key Project of Chinese Ministry of Education (No. 211055)Shanghai Research Special Fund for Outstanding Young Teachers (No. sdl10009)
文摘A systematic study on the structural, magnetic, and electrical transport properties was performed for the LaMnlxCUxO3 system. A single phase of orthorhornbic perovskite structure was formed for x = 0.05-0.40. A striking paramagnetic-ferromagnetic transition and a considerable magnetoresistance effect were observed at the ferromagnetic ordering temperature Tc, but no insulator-metal transition induced by Cu-doping was observed. Below Tc, a visible unexpected drop was observed in the ac susceptibility and zero-field-cooled dc magnetization for the dilute doped samples with x≤0.10, which was proven to be associated with domain wall pinning effects by milling the bulk material into single domain particles. It is validated that there is no exchange interaction between Cu and Mn, and double exchange interactions between Mn^3＋ and Mn^4＋ are induced by Cu-doping in the anti-ferromagnetic LaMnO3 matrix, whereas the severe distortion and disorder caused by occupied-dopant prohibits charge carriers from hopping.
文摘A new thin film pulse transformer for using in ISND and ADSL systems has been designed based on a domain wall pinning model, the parameters of nano-magnetic thin film such as permeability and coercivity can be calculated. The main properties of the thin film transformer including the size, parallel inductance, Q value and turn ratio have been simulated and optimized. Simulation results show that the thin film transformer can be fairly operated in a frequency range of 0.001~20 MHz.
