Cluster spin glass state caused by antiphase boundaries in NiFeGa alloys
Cluster spin glass state caused by antiphase boundaries in NiFeGa alloys
复制标题
NiFeGa合金中反相边界引起的团簇自旋玻璃态
DOI：
10.1016/j.jallcom.2018.03.161
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发表时间：
2018
影响因子：
6.2
通讯作者：
G.H. Wu
中科院分区：
文献类型：
--
作者：
Y.J. Zhang;Q.Q. Zeng;Z.Y. Wei;Z.P. Hou;Z.H. Liu;E.K. Liu;X.K. Xi;W.H. Wang;X.Q. Ma;G.H. Wu
本文报道了NiFeGa铁磁形状记忆合金的磁玻璃化性质的观察。Ni_(50)Fe_(21)Ga_(29)在27 K附近观察到团簇自旋玻璃转变。这种玻璃性源于由反相界(APB)隔开的细小磁区的冻结。由于APBS的钉扎效应，观察到居里温度以下的磁化强度降低。钉扎区产生很大的饱和场，在低场时磁化强度几乎是随机分布的。在动态磁测量的基础上，利用Vogel-Fulcher定律和幂定律研究了自旋-玻璃化转变的频率依赖性。在冻结温度以下，观察到了老化现象，并用拉伸指数函数来描述。这些理论研究证实了团簇自旋玻璃态的存在，这种自旋玻璃态起源于受阻磁畴之间的强相互作用。
We report an observation of magnetic glassy properties in NiFeGa ferromagnetic shape memory alloys. A cluster spin glass transition was observed at approximately 27 K in Ni50Fe21Ga29. The glassy property originates from the freezing of fine magnetic domains separated by antiphase boundaries (APBs). Due to the pinning effect of the APBs, depression of the magnetization just below the Curie temperature was observed. The pinned domains induce very large saturation fields and a nearly random distribution of magnetization in low field. Based on dynamic magnetic measurements, the frequency dependence of the spin-glass transition was investigated by using the Vogel-Fulcher law and a power law. Below the freezing temperature, an aging phenomenon was observed and described by stretched exponential functions. These theoretical investigations confirm the cluster spin-glass state, which originates from a strong interaction between the frustrated magnetic domains.