The influence of atomic order on the magnetic and structural properties of the ferromagnetic shape memory compound Ni2MnGa
The influence of atomic order on the magnetic and structural properties of the ferromagnetic shape memory compound Ni2MnGa
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DOI：
10.1088/0953-8984/15/22/317
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发表时间：
2003-05
期刊：
影响因子：
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通讯作者：
M. Kreissl;K. Neumann;T. Stephens;K. Ziebeck
中科院分区：
文献类型：
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作者：
M. Kreissl;K. Neumann;T. Stephens;K. Ziebeck
在1000℃淬火样品中，研究了原子顺序对化学计量Ni2MnGa马氏体相变和磁性能的影响。磁化、电阻率和x射线衍射测量表明，结构相变发生在~ 103 K，大大低于在800℃淬火并按Heusler L21结构排列的样品所报告的值。虽然居里温度在很大程度上没有受到影响，但铁磁力矩也有小幅下降。从热容测量得到的电子索默菲尔德系数有所提高，但小于800℃淬火样品的电子索默菲尔德系数。结果与能带结构计算和原子无序引起的电子变化一致。
The effect of atomic order on the martensitic phase transition and magnetic properties of stoichiometric Ni2MnGa has been investigated in a sample quenched from 1000 °C. Magnetization, resistivity and x-ray diffraction measurements indicate that the structural phase transition occurs at ~ 103 K, substantially lower than the value reported for samples quenched from 800 °C and ordered in the Heusler L21 structure. A small reduction in the ferromagnetic moment was also observed, although the Curie temperature remained largely unaffected. The electronic Sommerfeld coefficient obtained from heat capacity measurements is enhanced but smaller than that observed for the 800 °C quenched sample. The results are consistent with band structure calculations and the electronic changes brought about by atomic disorder.