不同磁相纳米颗粒膜的巨磁电阻

GIANT MAGNETORESISTANCE OF NANO-GRANULAR ALLOYS WITH DISTINCT MAGNETIC PHASES

用玻恩（Ｂｏｒｎ）散射方法计算了具有两类不同磁相的颗粒膜的巨磁电阻（ＧＭＲ），结果表明，在低温（４．５Ｋ），小磁性颗粒（包含原子数ｎ≤ １２）对巨磁电阻只有很小的贡献，巨磁电阻值随颗粒包含原子数的增多而增加在室温下，巨磁电阻主要由大磁性颗粒（ｎ １２）产生理论计算较好地解释了实验所观测到的结果．

The giant magnetoresistance (GMR) of magnetic granular films with two distinct phases was calculated by using Born approximation. The results showed that at low temperature (T=4.5K) small clusters contained magnetic atom number n <12 had only a minor contribution to the GMR and the GMR increased with number of the atoms. At room temperature, large magnetic granules (n >>12) dominated the GMR. The theoretical calculation interpreted well the experimental observation reported.