Successive phase transitions to antiferromagnetic and weak-ferromagnetic long-range order in the quasi-one-dimensional antiferromagnet Cu 3 Mo 2 O 9
Successive phase transitions to antiferromagnetic and weak-ferromagnetic long-range order in the quasi-one-dimensional antiferromagnet Cu 3 Mo 2 O 9
复制标题
DOI：
10.1103/physrevb.77.134419
复制
发表时间：
2008-03
影响因子：
3.7
通讯作者：
T. Hamasaki;T. Ide;H. Kuroe;T. Sekine;M. Hase;I. Tsukada;T. Sakakibara
中科院分区：
文献类型：
--
作者：
T. Hamasaki;T. Ide;H. Kuroe;T. Sekine;M. Hase;I. Tsukada;T. Sakakibara
对具有反铁磁（AF）线性链与反铁磁二聚体相互作用的${\mathrm{Cu}}_{3}{\mathrm{Mo}}_{2}{\mathrm{O}}_{9}$单晶的磁性进行了研究，发现在${T}_{N}=7.9\phantom{\rule{0.3em}{0ex}}\mathrm{K}$处发生了反铁磁二级相变。虽然弱铁磁类行为出现在较低的温度和低磁场中，但在$0.5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$以下无法检测到完全剩余磁化。然而，当沿$a$轴的微小磁场反转时，在${T}_{c}\ensuremath{\simeq}2.5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$处弱铁磁（WF）相变下的磁化强度出现跳变，表明矫顽力非常弱。与链平行的磁矩分量在${T}_{N}$以下形成AF长程有序（LRO），而垂直分量在零磁场下在${T}_{c}$以上无序，在${T}_{c}$以下形成WF-LRO。此外，WF-LRO也是通过在${T}_{c}$和${T}_{N}$之间施加磁场实现的。这些结果可以用对称交换相互作用之间的磁挫败和对称与不对称Dzyaloshinskii \char 21Moriya交换相互作用之间的竞争来解释。{}
Investigation of the magnetism of ${\mathrm{Cu}}_{3}{\mathrm{Mo}}_{2}{\mathrm{O}}_{9}$ single crystal, which has antiferromagnetic (AF) linear chains interacting with AF dimers, reveals an AF second-order phase transition at ${T}_{N}=7.9\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. Although weak-ferromagnetic-like behavior appears at lower temperatures in low magnetic fields, complete remanent magnetization cannot be detected down to $0.5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. However, a jump is observed in the magnetization below weak-ferromagnetic (WF) phase transition at ${T}_{c}\ensuremath{\simeq}2.5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ when a tiny magnetic field along the $a$ axis is reversed, suggesting that the coercive force is very weak. A component of magnetic moment parallel to the chain forms AF long-range order (LRO) below ${T}_{N}$, while a perpendicular component is disordered above ${T}_{c}$ at zero magnetic field and forms WF-LRO below ${T}_{c}$. Moreover, the WF-LRO is also realized by applying magnetic fields even between ${T}_{c}$ and ${T}_{N}$. These results are explainable by both magnetic frustration among symmetric exchange interactions and competition between symmetric and asymmetric Dzyaloshinskii\char21{}Moriya exchange interactions.