论文标题
反铁磁拓扑绝缘子MNBI $ _2 $ te $ _4 $基于对称性及其X射线光电子光谱法
The Layer-inserting Growth of Antiferromagnetic Topological Insulator MnBi$_2$Te$_4$ Based on Symmetry and Its X-ray Photoelectron Spectroscopy
论文作者
论文摘要
抗磁性拓扑绝缘子最近引起了很多关注，因为它的内在磁性和拓扑特性使其成为一种在相对高温下实现量子异常霍尔效应（QAHE）的潜在材料。到目前为止，仅预测并成功地生长了MNBI $ _2 $ TE $ _4 $。预测的其他MB $ _2 $ t $ _4 $ - family材料（MB $ _2 $ _2 $ _4 $：M =过渡金属或稀土元素，B = BI或SB，T = TE，SE或S）具有不仅具有抗folomagogogication属性，而且不仅具有抗formotic topologication属性，而且还完全具有良好的量子和动态化的结构（或者都具有动态化的结构）。在这里，MNBI $ _2 $ TE $ _4 $单晶已成功地生长并进行了测试。它显示了典型的抗铁磁特征，Neel温度为24.5K，并且在H $ \ thempapprox $ 35000 OE（1.8K）时进行了自旋流动过渡。在获得MNBI $ _2 $ TE $ _4 $单晶后，我们试图合成MB $ _2 $ _2 $ t $ _4 $ _4 $ family材料的其他成员，但是情况并不顺利。然后，它激发了我们讨论MNBI $ _2 $ TE $ _4 $的增长机制。生长模式可以是基于对称性的层插入生长模式，该模式由我们的X射线光电子光谱（XPS）测量支持。用$ ar^+$ $离子溅射的XPS测量梳理是为了调查MNBI $ _2 $ TE $ _4 $的化学状态。 MNBI $ _2 $ TE $ _4 $相关的MN2P和TE3D Spectra的绑定能量（BE）与插入材料$α$ -MNTE的捐款非常吻合。已经观察到使用原子数（从MNO到MNBI $ _2 $ _2 $ te $ _4 $）的MN2P卫星的强度上升，因此已观察到MNBI $ _2 $ _4 $ _4 $作为Charge-Cons-Transsfer compionge compoint。了解MNBI $ _2 $ TE $ _4 $的增长模式可以帮助我们种植MB $ _2 $ t $ _4 $ $ _4 $ - 家族材料的其他成员。
The antiferromagnetic topological insulator has attracted lots of attention recently, as its intrinsic magnetism and topological property makes it a potential material to realize the quantum anomalous Hall effect (QAHE) at relative high temperature. Until now, only MnBi$_2$Te$_4$ is predicted and grown successfully. The other MB$_2$T$_4$-family materials predicted (MB$_2$T$_4$:M=transition-metal or rare-earth element, B=Bi or Sb, T=Te, Se, or S) with not only antiferromagnetic topological property but also rich and exotic topological quantum states and dynamically stable (or metastable) structure have not been realized on experiment completely. Here, MnBi$_2$Te$_4$ single crystals have been grown successfully and tested. It shows typical antiferromagnetic character, with Neel temperature of 24.5K and a spin-flop transition at H$\thickapprox$35000 Oe, 1.8K. After obtaining MnBi$_2$Te$_4$ single crystals, we have tried to synthesize the other members of MB$_2$T$_4$-family materials, but things are not going so well. Then it inspires us to discuss the growth mechanism of MnBi$_2$Te$_4$. The growth mode may be the layer-inserting growth mode based on symmetry, which is supported by our X-ray photoelectron spectroscopy (XPS) measurement. The XPS measurement combing with the $Ar^+$ ion sputtering is done to investigate the chemical state of MnBi$_2$Te$_4$. Binding energies (BE) of the MnBi$_2$Te$_4$-related contributions to Mn2p and Te3d spectra agree well with those of inserting material $α$-MnTe. Rising intensity of the Mn2p satellite for divalent Mn (bound to chalcogen) with atomic number of ligand (from MnO to MnBi$_2$Te$_4$) has been observed, thus suggesting classification of MnBi$_2$Te$_4$ as the charge-transfer compound. Understanding the growth mode of MnBi$_2$Te$_4$ can help us to grow the other members of MB$_2$T$_4$-family materials.
