Magnetic ordering and frustration in hexagonal UNi4B.
Magnetic ordering and frustration in hexagonal UNi4B.
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六边形 UNi4B 中的磁排序和挫败。
DOI：
10.1103/physrevlett.73.1031
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发表时间：
1994
影响因子：
8.6
通讯作者：
J. Mydosh
中科院分区：
文献类型：
--
作者：
S. Mentink;A. Drost;G. Nieuwenhuys;E. Frikkee;A. Menovsky;J. Mydosh
用中子衍射方法测定了六方铀金属间化合物U Ni 4 B的异常磁序。在易基面上，U矩具有三角对称性，并存在反铁磁相互作用。沿着硬c轴发生铁磁耦合。在T N= 20 K以下，在第三顺磁自旋周围的类涡旋排列中，每三个U矩中只有两个是1.2 μ B阶。这种新的磁性结构与晶体学超结构的出现有关。以前观察到的异常体性能低于TN归因于非常规的自旋波激发与这种类型的订购。
We have determined unusual magnetic ordering of the hexagonal intermetallic uranium compound U N i 4 B via neutron diffraction. In the easy basal plane the U moments have triangular symmetry with antiferromagnetic interactions. Along the hard c axis ferromagnetic coupling occurs. Below T N= 20 K only two out of every three U moments of 1.2 μ B order in vortexlike arrangements around the third paramagnetic spin. This novel magnetic structure is related to the occurrence of a crystallographic superstructure. Previously observed anomalies in bulk properties below T N are attributed to unconventional spin-wave excitations associated with this type of ordering.