Ni_(79)Fe_(21)-Al_2O_3纳米颗粒膜的电、磁性质

The Electric and Magnetic Properties of Ni_(79)Fe_(21)-Al_2O_ 3 Nano-Granular Films

采用磁控溅射法在玻璃基片上制备了一系列不同Ni79Fe2 1含量x的 (Ni79Fe2 1) x(Al2 O3) 1-x纳米颗粒膜样品 .研究了电阻率 ρ与体积百分比x的关系 ,测出了逾渗阈值xρ,并对样品的巨磁电阻效应和霍尔效应进行了研究 .发现存在三个区间 :(1)当x <48%时 ,在这个区间只有巨磁电阻效应 ,没有霍尔效应 ;(2 )当 48% <x <6 0 %时 ,在这个区间巨磁电阻效应和霍尔效应共存 ,且随着x的减小而增强 ;(3)当x >6 0 %时 ,在这个区间只有霍尔效应 ,没有巨磁电阻效应 .

A series of (Ni 79Fe 21) x-(Al 2O 3) 1-x nano-granular films have been fabricated on glass substrates by magneto sputtering technique. The percolation threshold x ρ of about 60% has been measured through the curve of ρ and x v. The giant magnetoresistance and hall effect have been studied at room temperature . (Ni 79Fe 21) x-(Al 2O 3) 1-x nano-granular films will exhibit both GMR and GHE, and both effects increase with the decrease of x v in the region 0.48<x<0.60.While the sample exhibits only Hall effect for x v>0.60,and only GMR effect for x v<0.48.