Effective Exchange Constant and Electronic Structure of Pseudo-Gap-Type L10-MnPd Alloys
Effective Exchange Constant and Electronic Structure of Pseudo-Gap-Type L10-MnPd Alloys
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赝带隙型L10-MnPd合金的有效交换常数和电子结构
DOI：
10.1143/jpsj.75.104714
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发表时间：
2006
影响因子：
1.7
通讯作者：
A. Sakuma
中科院分区：
文献类型：
--
作者：
R. Umetsu;K. Fukamichi;A. Sakuma
对Pd含量为40%~60%的L 1 0 型MnPd合金体系进行了电阻率、磁力和低温比热测量以及理论计算。在目前的反铁磁合金体系中，在Pd浓度为53%附近观察到最高尼尔温度T N ，偏离了等原子浓度。这种行为也符合有效交换常数 J 0 的理论计算，该常数给出了 T N 的值。在L 1 0 型MnPd合金的电阻率的温度依赖性中，观察到刚好低于T N 的驼峰的特征行为，这与赝能隙型反铁磁体有关。此外，电子比热系数γ e 的值显着小于1 mJ mol -1 K -2 且高于50% Pd，反映了费米能E F 处的态密度非常低。磁矩与鲍林价之间的线性关系...
The electrical resistivity, magnetic and low-temperature specific heat measurements, and theoretical calculations for L 1 0 -type MnPd alloy system were carried out in a wide range of composition from 40 to 60% Pd. In the present antiferromagnetic alloy system, the highest Neel temperature T N was observed in the vicinity of 53% Pd concentration, deviating from the equiatomic concentration. This behavior was also conformed by the theoretical calculations for the effective exchange constant J 0 which gives the value of T N . In the temperature dependence of electrical resistivity for the L 1 0 -type MnPd alloys, a characteristic behavior of a hump just below T N was observed, which is associated with the pseudo-gap-type antiferromagnets. In addition, the value of the electronic specific heat coefficient γ e is significantly small below 1 mJ mol -1 K -2 above 50% Pd, reflecting the very low density of states at the Fermi energy E F . The linear relation between the magnetic moment and the Pauling valence ha...