Tb_(1-x)Gd_xFe_2的磁矩和矫顽力  

MAGNETIC MOMENTS AND COERCIVE FORCE OF Tb_(1-x)Gd_xFe

作　　者：钟文定[1] 刘尊孝[1] 

机构地区：[1]北京大学物理系,北京100871

出　　处：《物理学报》1992年第6期1005-1011,共7页Acta Physica Sinica

基　　金：国家自然科学基金

摘　　要：测量了赝二元立方Laves相化合物TbGdFe_2(0≤x≤1)的磁化曲线、居里温度和矫顽力随温度的变化。发现化合物由TbFe_2向GdFe_2过渡时,样品的饱和磁化强度几乎直线下降。在所有成分下,Fe原子的磁矩都是常数(μFe=1.60±0.04μB ),但Tb原子的磁矩,由于受晶场影响,却小于自由离子的值(J=9.OμB)。矫顽力由两部分组成:一为畴壁受Peierls势垒和稀土晶位上磁晶各向异性涨落的内禀钉扎,这部分的贡献在低温下占优势,随温度升高便指数衰减;另一为内应力引起的自由磁极,对畴壁的钉扎。The magnetization curves, the Curie temperature and the thermal dependence of the coercive force in the pseudobinary cubic Laves phase compounds Tb1-xGdzFe2(0≤x≤l) has been measured. The saturation magnetization decreases almost linearly from TbFe2 to GdFe2. The magnetic moment of the iron atoms is a constant(μFc -1.60±0.04μB) for the whole concentration range, while the moment of terbium atoms is smaller slightly than its free ion value of gJ = 9.0μB due to crystal-field effects. The coercive field has got two contributions: one cames from the intrinsic pinning of domain walls in the Peierls crystal pontential wells and the fluctuation of magnetocrystalline anisotropy at rare-earth site; this contribution is preponderant at low temperatures, decaying exponentially with increasing temperature. The other comes from the pinning of domain walls by the internal stresses, causing the appearance of free magnetic poles.

关 键 词：稀土元素 化合物 磁矩 矫顽力 

分 类 号：O482.5[理学—固体物理]