Spin dependent impurity effects on the 2D frustrated magnetism of NiGa2S4.
Spin dependent impurity effects on the 2D frustrated magnetism of NiGa2S4.
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DOI：
10.1103/physrevlett.101.207204
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发表时间：
2008-04
影响因子：
8.6
通讯作者：
Y. Nambu;S. Nakatsuji;Y. Maeno;Edem K. Okudzeto;J. Chan
中科院分区：
文献类型：
--
作者：
Y. Nambu;S. Nakatsuji;Y. Maeno;Edem K. Okudzeto;J. Chan
研究了三角形反铁磁体Ni_（1-x）M_xGa_2S_4（M=Mn，Fe，Co，Zn）的杂质效应。NiGa 2S 4的二维冻结自旋无序态对Zn 2+（S=0）和Heisenberg Fe 2+（S=2）自旋的替代是稳定的，并且表现出由韦斯温度标度的T2依赖的磁比热。相反，Co ~（2+）（S=3/2）自旋的类Ising各向异性取代和Mn ~（2+）（S=5/2）自旋的Heisenberg取代在低于1 K的温度下诱导出常规的自旋玻璃相。从这些比较中，它表明，海森堡自旋的整数大小是重要的，以稳定在冻结自旋无序态中观察到的二维相干行为。
Impurity effects on the triangular antiferromagnets Ni1-xMxGa2S4 (M=Mn, Fe, Co and Zn) are studied. The 2D frozen spin-disordered state of NiGa2S4 is stable against the substitution of Zn2+ (S=0) and Heisenberg Fe2+ (S=2) spins, and exhibits a T2-dependent magnetic specific heat, scaled by the Weiss temperature. In contrast, the substitutions with Co2+ (S=3/2) spin with Ising-like anisotropy and Heisenberg Mn2+ (S=5/2) spin induce a conventional spin glass phase below 1 K. From these comparisons, it is suggested that the integer size of the Heisenberg spins is important to stabilize the 2D coherent behavior observed in the frozen spin-disordered state.