论文标题
连续的电介质异常和磁电耦合蜂窝fe $ _4 $ nb $ _2 $ o $ _9 $
Successive dielectric anomalies and magnetoelectric coupling in honeycomb Fe$_4$Nb$_2$O$_9$
论文作者
论文摘要
通过结合单晶体X射线和中子衍射，以及在单晶Fe4NB2O9上的磁纤维测量值，我们提出了Fe4NB2O9中的磁性结构和对称允许的磁性偶联。它在Tn = 93 K处进行抗铁磁过渡，然后在Ts = 70 K处进行可变的过渡。Fe4NB2O9的温度依赖性介电常数强烈各向异性，其第一个异常在93 k处，由于较长范围的序列，并在93 k中均在93 K上进行了序列，并在70 k上进行了70 k的序列，该阶段的序列是70 k Eman，eman eman artiration the ryan tr in n y n a in y0 k eman artiration tr in y n y0 k eman artiration the n ar y eman artiratient y eman artiratient y eman eman y0 eman y0 eman y0 eman y0，原子位移。在单晶Fe4NB2O9中观察到磁场诱导的磁电耦合，并且与蜂窝平面中抗磁性布置的铁磁链的特征的已解决的磁性结构兼容。我们建议，这种磁对称性应在一定程度上免受外部磁场的影响，这是由于蜂窝平面中矩旋转的自由度所带来的，这制定了一个有希望的系统，以控制磁场。
By combining single crystal x-ray and neutron diffraction, and the magnetodielectric measurements on single crystal Fe4Nb2O9, we present the magnetic structure and the symmetry-allowed magnetoelectric coupling in Fe4Nb2O9. It undergoes an antiferromagnetic transition at TN=93 K, followed by a displacive transition at TS=70 K. The temperature-dependent dielectric constant of Fe4Nb2O9 is strongly anisotropic with the first anomaly at 93 K due to the exchange striction as a result of the long range spin order, and the second one at 70 K emanating from the structural phase transition primarily driven by the O atomic displacements. Magneticfield induced magnetoelectric coupling was observed in single crystal Fe4Nb2O9 and is compatible with the solved magnetic structure that is characteristic of antiferromagnetically arranged ferromagnetic chains in the honeycomb plane. We propose that such magnetic symmetry should be immune to external magnetic fields to some extent favored by the freedom of rotation of moments in the honeycomb plane, laying out a promising system to control the magnetoelectric properties by magnetic fields.
