Magnetic neutron scattering from quasicrystalline Zn-Mg-Ho and Zn-Mg-Y at low temperatures
Magnetic neutron scattering from quasicrystalline Zn-Mg-Ho and Zn-Mg-Y at low temperatures
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低温下准晶 Zn-Mg-Ho 和 Zn-Mg-Y 的磁中子散射
DOI：
10.1016/s0921-5093(00)01068-6
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发表时间：
2000
期刊：
影响因子：
6.4
通讯作者：
R. Lechner
中科院分区：
文献类型：
--
作者：
M. Scheffer;M. Rouijaa;J. Suck;R. Sterzel;R. Lechner
与其他准周期合金中的磁性过渡金属离子相比，二十面体Zn-Mg-RE中的RE（RE=稀土）离子由于局部4f电子而显示出局部磁矩。这些矩的长程和短程序仍在讨论中。为了研究这些Frank-Kasper型fci结构的磁性，我们在1.6和25.0K之间的温度下进行了非弹性中子散射实验，并测量了直流磁化率。结果表明样品的散射主要是顺磁散射。与Zn-Mg-Y的数据的比较确保，所观察到的散射不是声子或相位性质的。准弹性峰的线形可以用位移洛伦兹函数来模拟。观察到的位移很小（约0.6meV），没有表现出色散。线宽在Q中是恒定的，并且随温度而增加。这种行为的一个可能的解释是存在一个晶体场分裂。
In contrast to the magnetic transition metal ions in other quasiperiodic alloys, the RE (RE=rare earth) ions in icosahedral Zn–Mg–RE show localised magnetic moments due to localised 4f electrons. Long range as well as short range order of these moments are still under discussion. To investigate the magnetic properties of these fci-structures of Frank–Kasper type, we performed inelastic neutron scattering experiments at temperatures between 1.6 and 25.0K and measured the DC magnetic susceptibility. The results show mainly paramagnetic scattering of the samples. Comparison with the data of Zn–Mg–Y ensures, that the observed scattering is not of phononic or phasonic nature. The lineshape of the quasielastic peak can be modeled by a shifted Lorentzian. The observed shift is small (approximately 0.6meV) and shows no dispersion. The linewidth is constant in Q and increases with temperature. A possible interpretation of this behaviour is the existence of a crystal field splitting.