标题：The Phenomenon of Positive Magnetoimpedance in La0.75Sr0.25MnO3 PLD Film
作者：Wang, Yifei; Liu, Hua; Hu, Jifan
作者机构：[Wang, Yifei; Liu, Hua; Hu, Jifan] Shandong Univ, Sch Phys, State Key Lab Crystal Mat, Jinan 250100, Peoples R China.
会议名称：Progress In Electromagnetics Research Symposium
会议日期：SEP 12-16, 2011
来源：PIERS 2011 SUZHOU: PROGRESS IN ELECTROMAGNETICS RESEARCH SYMPOSIUM
摘要：In the present work, La0.75Sr0.25MnO3 polycrystalline film was grown on Si (1 0 0) substrate by pulsed laser deposition. Negative magnetoimpedance Delta Z/Z(0) = -2.64% was obtained under a low field of 500 Oe for the film with an 800 degrees C annealing. For the film with a liquid nitrogen treatment after an 800 degrees C annealing, a positive magnetoimpedance occurs at 10 MHz. The peak value of Delta Z/Z(0) is 48.1% under 200 Oe. We suggested that the negative magnetoimpedance for the film with 800 degrees C annealing is connected with a decrease of permeability induced by DC low fields, whereas the positive magnetoimpedance for the film with liquid-nitrogen treatment was connected with an increase of permeability with field, due to the existence of transverse anisotropy developed in the film during the liquid-nitrogen treatment process. With Machado-Rezende model on magnetic domain motion, we calculated the field dependence of transverse susceptibility x. When a transverse anisotropy field H-A exists, the transverse susceptibility x should have a peak at a field H = H-A.