磁场作用下PMN-PT/CFO的磁电效应研究

Research of the magnetoelectric effect of PMN-PT/CFO in magnetic field

在弹性力学模型下,推导非理想耦合状态的磁电(ME)电压系数公式.利用CoFe2O4(CFO)随磁场变化的磁致伸缩特性,得到Pb(Mg1/3Nb2/3)O3-PbTiO3(PMN-PT)与CFO复合材料的磁电电压系数随磁场以及各参量的变化关系公式.研究了磁电电压系数在磁场下随磁场强度、压电相体积分数v、界面耦合系数k以及PMN-PT介电常数之间的变化关系.研究结果发现:磁电电压系数随PMN-PT体积分数和磁场强度的增大,表现为先增大,后逐渐减小至零;磁电电压系数强烈地依赖于界面耦合系数,耦合系数减小会极大降低复合材料的磁电效应;同时,磁电效应具有一定的频率特性,随着频率的逐渐增大而增大,直至达到稳定.

In terms of elasticity mechanical theory model ,the magnetoelectric voltage coefficient formula is estab-lished ,using the magnetostrictive properties of CoFe2 O4 （CFO） in the magnetic field ,we obtain the changing re-lations of Pb（Mg1/3 Nb2/3 ） O3 -PbTiO3 （PMN-PT ）/CFO magnetoelectric voltage coefficient changing with the magnetic field and other parameters .The magnetoelectric voltage coefficient is also studied as the function of the Magnetic field intensity 、PMN-PT volume fraction v、interface coupling coefficient k and PMN -PT dielectric constant in magnetic field .The results show that the magnetoelectric voltage coefficient increase firstly ,then gradually decreases to zero with the increase of PMN -PT volume fraction and magnetic intensity ;the magneto-electric voltage coefficient strongly depends on the interface coupling coefficient ,which will largely reduce mag-netoelectric effect ;Meanwhile ,Magnetoelectric effect has a certain frequency characteristic ,with the increase of frequency ,which increase gradually and reaches stability .