磁性颗粒复合介质中磁电阻机制诱导的庞磁电容效应  

Colossal magnetocapacitance induced by magnetoresistance effects in magnetic particle composite systems

作　　者：朱云[1] 雎胜[2] 

机构地区：[1]苏州大学物理科学与技术学院,江苏苏州215006 [2]江南大学理学院物理系,江苏无锡214122

出　　处：《苏州大学学报（自然科学版）》2006年第4期56-60,共5页Journal of Soochow University(Natural Science Edition)

基　　金：国家自然科学基金资助项目(10474069;10504023)

摘　　要：最近的实验和理论研究表明,磁电阻效应结合Maxwell-Wagner电路模型,磁性颗粒复合介质中也可能产生庞磁电容效应.这种庞磁电容效应与传统的磁电材料中由于直接的磁电耦合机制而产生的磁电容效应不同,它将会具有很高的实际应用价值.从磁性颗粒复合体系微观结构出发,应用Maxwell-Garnett理论(MGT)和磁电阻机制,研究了磁性颗粒复合体系中的庞磁电容效应随外加磁场和组分浓度p的变化关系,很好地解释了实验结果.In recent research, colossal magnetocapacitance can be achieved through a bombination of magnetoresistance and Maxwell-Wagner effect in magnetic particle composite systems. This magnetocapacitance effect is different with which directly induced by magnetoelectric coupling in conventional materials, which will be advantageous for practical applications. Based on magnetic particle composite systems as well as magnetoresistance mechanism, the frequency dependent manetocapacitance and magnetocapacitance as a function of the volume or area fraction of the inclusions p were investigated, employing the effective-medium theory for asymmetry （MGT） microscopic structure. Our calculations explain the experimental results well.

关 键 词：庞磁电容 磁电阻效应 MGT 复合体系 

分 类 号：O469[理学—凝聚态物理]