Spin dynamics of triangular lattice antiferromagnet CuFeO 2 : Crossover from spin-liquid to paramagnetic phase
Spin dynamics of triangular lattice antiferromagnet CuFeO 2 : Crossover from spin-liquid to paramagnetic phase
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DOI：
10.1103/physrevb.80.144413
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发表时间：
2009-10
影响因子：
3.7
通讯作者：
K. Hayashi;T. Nozaki;R. Fukatsu;Y. Miyazaki;T. Kajitani
中科院分区：
文献类型：
--
作者：
K. Hayashi;T. Nozaki;R. Fukatsu;Y. Miyazaki;T. Kajitani
我们通过测量粉末中子非弹性散射谱研究了三角晶格反铁磁体 ${\text{CuFeO}}_{2}$ 的自旋动力学。其半宽度随着散射矢量的大小而振荡的准弹性分量出现在高于 N'eel 温度的光谱中。代表准弹性成分形状和振荡行为的动力学模型随着温度的升高从自旋跳跃扩散变化到海森堡顺磁 (PM) 散射。这些发现表明 ${\text{CuFeO}}_{2}$ 显示出从自旋液相到海森堡 PM 相的逐渐转变。自旋液相的起源是根据不相称的短程自旋相关性来讨论的。
We have investigated the spin dynamics of triangular lattice antiferromagnet ${\text{CuFeO}}_{2}$ by measuring powder neutron inelastic-scattering spectra. A quasielastic component whose half-width oscillates with the magnitude of the scattering vector appears in the spectra above N\'eel temperature. A dynamics model representing the shape of quasielastic components and oscillatory behaviors changes from spin jump diffusion to Heisenberg paramagnetic (PM) scattering with increasing temperature. These findings demonstrate that ${\text{CuFeO}}_{2}$ shows a gradual transition from a spin-liquid phase to the Heisenberg PM phase. The origin of the spin-liquid phase is discussed in terms of incommensurate short-range spin correlation.