Strong Effect of Yb Filling Fraction on the Magnetic Ground Sate of the Filled Skutterudite YbFe4Sb12
Strong Effect of Yb Filling Fraction on the Magnetic Ground Sate of the Filled Skutterudite YbFe4Sb12
复制标题
Yb 填充分数对填充方钴矿 YbFe4Sb12 磁基态的强烈影响
DOI：
10.1143/jpsj.80.063708
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
T.SAITO
中科院分区：
文献类型：
--
作者：
荘涛;平岡耕一;小島健一;鬼丸孝博;高畠敏郎;T.SAITO
采用Sb自熔法在4GPa压力下成功合成了Yb位填充率接近100%的YbFe_4Sb_（12）单晶。生长的单晶体不表现出铁磁有序下降到最低温度调查，与铁磁转变报道的Yb-缺陷的单晶体在环境压力下生长。本晶体的电子比热系数明显小于报道的Yb缺陷样品，表明费米能位于由Fe-3d电子的贡献占主导地位的电子态密度的峰值的高能侧。因此，在Yb缺陷样品中的铁磁状态的外观可以在简单的Stoner型参数内天真地理解。在传导电子的自旋涨落散射占主导地位的温度区域，发现正磁电阻的显着增强。
YbFe4Sb12single crystals with the Yb-site filling fraction close to 100% have been successfully synthesized by the Sb self-flux method under a pressure of 4 GPa. The grown single crystals do not exhibit ferromagnetic ordering down to the lowest temperature investigated, in contrast with the ferromagnetic transition reported for Yb-deficient single crystals grown at ambient pressure. The electronic specific heat coefficient of the present crystals is evidently smaller than those reported for Yb-deficient samples, indicating that the Fermi energy is located at the high-energy side of a peak in the electronic density of states dominated by the contribution of Fe-3d electrons. Therefore, the appearance of the ferromagnetic state in the Yb-deficient samples can be naively understood within the simple Stoner-type argument. Marked enhancement of the positive magnetoresistance was found in the temperature region where the spin-fluctuation scattering of conduction electrons dominates.