NiMnSb半金属材料的临界指数及临界特征

Critical Exponential Character of Half-metallic NiMnSb Materials

在不同磁场下根据磁化强度与温度的关系,测定和研究了半金属NiMnSb块体材料的临界指数,精确求得居里温度TC=731 K,磁化率临界指数γ=1.12和有序临界指数β=0.482.实验结果表明半金属NiMnSb材料的临界特征符合铁磁理论的平均场模型.

Critical exponents of the NiMnSb bulk materials have been investigated by measuring the temperature dependence of magnetization at different magnetic field. The critical temperature has been more accurately obtained to be Tc = 731 K. The critical exponents of γ and β for the initial susceptibility Xo^-1=C1 （T - Tc）^γ and the spontaneous magnetization M1= C2 （Tc-T）^β have been determined as 1.12 and 0. 482, respectively, indicating that the ferromagnetism of NiMnSb ean be fitted by mean field model.