非晶Fe89.7P10.3合金纳米线阵列的磁性研究

利用电化学沉积方法在阳极氧化铝模板中制备了Fe_89.7P_10.3非晶 合金纳 米线阵列.利用x射线衍射仪、透射电子显微镜、振动样品磁强计和穆斯堡尔谱仪研究了样品的结构和磁性,发现纳米线阵列是非晶结构，且拥有垂直磁各向异性和高的矫顽力，H_c =304×10⁴A/m.纳米线内部的平均超精细场和平均同质异能移分别为2 15×10⁶ A/m和007 mm/s；而纳米线末端的平均超精细场（233×10⁶ A/m ）大于内 部的值，平均同质异能移（004 mm/s）小于内部的值.另外，纳米线内部Fe原子磁矩与线轴的夹角约为16°，而在纳米线末端Fe原子磁矩与线轴的夹角约为28°.这些结果表明，由于形状各 向异性，在纳米线中实现了无序非晶合金磁矩的有序排列. 关键词： 非晶合金 纳米线阵列 垂直磁各向异性 穆斯堡尔谱

Magnetic properties of amorphous Fe89.7P10.3 alloy nanowire arrays

Amorphous Fe_89.7P_10.3 alloy nanowire arrays were fabri cated in an anodic aluminum oxide template by means of electrodeposition. X-ray diffract ion, transmission electron microscopy, vibrating sample magnetometer and Mssbauer spectrometer are employed to study the structure and magnetic properties of the nanowire arrays. The results show that the nanowire arrays are amorphous with a perpendicular magnetic anisotropy and high coercivity H_c=304 ×10⁴ A/m. The mean hyperfine field and the mean isomer shift of the insi de of nanowires are 215×10⁶ A/m and 007 mm/s, respectively. The mean hype rfine field (233×10⁶ A/m) at the end of nanowires is higher than that of th e inside of nanowires, but the mean isomer shift (004 mm/s) at the end of nanowires is smaller than that of the inside of nanowires. The average angle between the Fe magentic moment and the wire axis is 16° in the the inside of nanowires, but the average angle is 28° at the end of nanowires. Due to the shape anisotropy of nanowires, the ordered alignment of magnetic moments is realized in the disordered amorphous alloy system.