摘要
研究了颗粒平均直径由9.1—860nm范围的锂铁氧体纳米晶的磁性.它们的比饱和磁化强度σ_s随其颗粒尺寸减小而线性减小.测量了样品A(颗粒直径为D=860nm),样品B(D=11.8nm)和样品C(D=9.1nm)的比饱和磁化强度随温度的变化曲线σ(T)和穆斯堡尔谱.发现样品B和C的居里温度比样品A的低50℃.从样品C的σ(T)曲线看,样品C好像由二种磁相所构成.利用超顺磁和表面磁性讨论了样品C的特异磁性.
The magnetic properties of lithium ferrite nanocrystallites ranging from 9.1 to 860 nm have been studied. The specific saturation magnetization σs of these nanocrystallites decrease lineally with the nanocrystallite size.The specific magnetization versus temperature curves (T) and M(?)ssbauer spectra of sample A (diameter D = 860 nm), sample B (D = 11.8 nm) and sample C (D = 9.1 nm) have been measured. It is found that the Curie temperatures of samples B and C are 50℃ lower than that of sample A. From the σ(T) curve of sample C, it seems that sample C consists of two magnetic phases. These phenomena have been discussed with the superparamagnetism and the surface magnetism of sample C.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
1996年第2期291-296,共6页
Acta Physica Sinica