Fe-SiO_2颗粒膜中的磁电阻效应和霍耳效应  

TUNNELING MAGNETO-RESISTANCE EFFECT AND GIANT HALL EFFECT IN Fe-SiO_2 GRANULAR FILMS

作　　者：杨啸林[1] 席力[1] 李伟[1] 李成贤[1] 葛世慧[1] 

机构地区：[1]兰州大学磁学与磁性材料教育部重点实验室,甘肃兰州730000

出　　处：《真空与低温》2007年第1期21-24,共4页Vacuum and Cryogenics

基　　金：国家自然科学基金项目(批准号:50371034)资助

摘　　要：利用射频共溅射方法制备了一系列不同金属体积分数fv的Fe-SiO2金属-绝缘体颗粒膜。系统地研究了薄膜的微结构、磁性、隧道磁电阻效应(TMR)和巨霍耳效应(GHE)。在fv=0.33处得到最大磁电阻值为-3.3%,fv=0.52处饱和霍耳电阻率达最大值,为18.5μΩ.cm。在300℃以内的不同温度下将Fe0.52(SiO2)0.48颗粒膜回火,霍耳电阻率随温度的变化不大,即样品具有良好的热稳定性。这表明Fe0.52(SiO2)0.Fe-SiO2 metal-iusulator granular films with various metal volume fractions （fv） were fabricated by RF co-sputtering. The mlcrostructure and tunneling magneto-resistance （TMR） as well as the giant Hall effect （G- HE） were systematically investigated. The Fe0.33（ SiO2）0.67 film exhibits the largest TMR value of -3.3% at room temperature under 1.3 T magnetic field. The sample with fv=0.52 exhibits the largest Hall resistivity of 18.5 μΩ·cm. The Hall resistivity does not decrease much, when the Fe0.52（SiO2）0.48 granular film annealed at different temperature up to 300℃.It indicates a good thermal stability of GHE for this film. Thus the film may be considered as a magnetic field sensor for operating temperature below 300℃.

关 键 词：颗粒膜 隧道磁电阻效应 巨霍耳效应 

分 类 号：O484.43[理学—固体物理]