非晶态磁性合金的磁阻和磁击穿现象

在室温下磁场在0—15kOe范围内测量了非晶态磁性合金(Fe_1-xCo_x)₈₂Cu_0.4Si_4.4B_13.2的横向磁阻△ρ/ρ。发现在高磁场下,磁阻与磁场强度有三种函数关系:(1)磁阻趋于饱和;(2)磁阻随磁场平方正比地增加;(3)对x=0.15的合金,在特殊的电流、磁场方向和确定的磁场强度下,有磁阻尖峰出现。情况(3)是一种磁击穿现象。磁击穿发生在自旋向上和向下的两片Fer 关键词：

MAGNETORESISTANCE AND MAGNETIC BREAKDOWN PHENOMENON IN AMORPHOUS MAGNETIC ALLOYS

Transverse magnetoresistance in amorphous magnetic alloys (Fe_1-xCo_x)₈₂Cu_0.4Si_4.4B_13.2 were measured at room temperature and in the magnetic field range 0-15 kOe. For large magnetic field, three various functional dependences of magnetoresistance on magnetic field strength have been found as follows: (1) △ρ/ρ approaches saturation. (2) △ρ/ρ increases proportionally to H². (3) For x = 0.15, sharp △ρ/ρ peak appears at certain magnetic field strenght in spectial angular orientation of both magnetic and electric current. The case (3) is a magnetic breakdown phenomenon. Magnetic breakdown occurs at the gap between the spin-up and spin-down sheets of the Fermi surface. This gap is the spin-orbit gap and its magnitude is a sensitive function of magnetization. Hence the magnitude and wide of the magnetoresistance peak and the magnetic field strength at the peak point are functions of angular orientation of both magnetic field and electric current.