退火对Co_(35)(SiO_2)_(65)颗粒膜巨磁电阻效应的影响  

INFLUENCE OF ANNEALING TEMPERATURE ON THE GIANT MAGNETORESISTANCE OF Co_(35)(SiO_2)_(65)NANO GRANULAR FILMS 

作　　者：徐庆宇[1] 倪刚[1] 桑海[1] 都有为[1] 

机构地区：[1]南京大学固体微结构物理国家重点实验室,南京210093

出　　处：《物理学报》1999年第S1期52-55,共4页Acta Physica Sinica

基　　金：国家自然科学基金!( 批准号:19890310(4));国家攀登计划!( 纳米材料科学)( 批准号:NMS07) ;江苏省自然科学基

摘　　要：采用多靶离子束溅射镀膜机制备了一系列不同退火温度的Ｃｏ３５（ＳｉＯ２）６５（ 体积百分数） 颗粒膜样品，发现样品的巨磁电阻效应随着退火温度Ｔａ 的升高而单调下降．应用磁力显微镜对样品的磁结构进行了观测，发现随着退火温度的升高，近邻的Ｃｏ 颗粒的磁矩倾向于平行排列，形成磁畴结构，从而导致Ｃｏ３５（ＳｉＯ２）６５ 颗粒膜巨磁电阻效应单调下降．A series of Co\-\{35\}(SiO\-2)\-\{65\}(volume fraction) nano\|granular films of heat treatment at different annealing temperatures( T a) were fabricated using ion\|beam sputtering technique. The giant magnetoresistance of the samples was found to decrease with increasing annealing temperature. It was found that with increasing annealing temperature to 500?K, the magnetic domains of Co\-\{35\}(SiO\-2)\-\{65\} nano\|granular films were more and more clear, which showed that with increasing annealing temperature, the neighboring isolated Co particles tended to arrange their magnetic moments parallel to each other, thus led to the decrease of the giant magnetoresistance of Co\-\{35\}(SiO\-2)\-\{65\} nano\|granular films with increasing annealing temperature.

关 键 词：颗粒膜 退火温度 磁电阻效应 巨磁电阻 磁畴结构 国家重点实验室 磁力显微镜 铁磁颗粒 微结构 单调下降 

分 类 号：O484[理学—固体物理]