A series of Co-Ag granular films were deposited onto a glass substrate with a thickness on the order of 400nm using the ion-beam cosputtering technique.Granular films ranging in composition from about 0-100%fraction b...A series of Co-Ag granular films were deposited onto a glass substrate with a thickness on the order of 400nm using the ion-beam cosputtering technique.Granular films ranging in composition from about 0-100%fraction by volume of cobalt have been prepared.Polar Kerr rotation spectra of the films were measured at room temperature in the wavelength region between 400 and 850nm.A maximum Kerr rotation angle(θk)of 0.28ºwas obtained when a magnetic field of 10kOe was applied perpendicular to the film plane.Our results indicate that the Co particle density and the microstructure between the Co particles and Ag matrix may play an important role in the Kerr rotation.展开更多
Magnetic entropy change larger than that of gadolinium has been observed in perovskite manganese oxides La_(0.67-x)Gd_(x)Ca_(0.33)MnO_(3)(x=0,0.1,0.15)with fixed carrier concentration.The large magnetic entropy change...Magnetic entropy change larger than that of gadolinium has been observed in perovskite manganese oxides La_(0.67-x)Gd_(x)Ca_(0.33)MnO_(3)(x=0,0.1,0.15)with fixed carrier concentration.The large magnetic entropy change produced by the abrupt reduction of magnetization is attributed to the anomalous thermal expansion just at the Curie temperature.This phenomenon indicates potential applications for magnetic refrigerants in an extended high temperature range.展开更多
基金Supported by the Climbing Program(85-6 NMS)from National Commission of Science and Technology of China under Grant No.920232003the National Natural Science Foundation of China under Grant No.59671021。
文摘A series of Co-Ag granular films were deposited onto a glass substrate with a thickness on the order of 400nm using the ion-beam cosputtering technique.Granular films ranging in composition from about 0-100%fraction by volume of cobalt have been prepared.Polar Kerr rotation spectra of the films were measured at room temperature in the wavelength region between 400 and 850nm.A maximum Kerr rotation angle(θk)of 0.28ºwas obtained when a magnetic field of 10kOe was applied perpendicular to the film plane.Our results indicate that the Co particle density and the microstructure between the Co particles and Ag matrix may play an important role in the Kerr rotation.
基金Supported by the State Major Basic Research Project:Nano-materials Science,and the National Natural Science Foundation of China under Grant No.59671021.
文摘Magnetic entropy change larger than that of gadolinium has been observed in perovskite manganese oxides La_(0.67-x)Gd_(x)Ca_(0.33)MnO_(3)(x=0,0.1,0.15)with fixed carrier concentration.The large magnetic entropy change produced by the abrupt reduction of magnetization is attributed to the anomalous thermal expansion just at the Curie temperature.This phenomenon indicates potential applications for magnetic refrigerants in an extended high temperature range.
