论文标题
晶体生长和可能的新磁性拓扑绝缘子的表征Febi2Te4
Crystal Growth and characterization of possible New Magnetic Topological Insulators FeBi2Te4
论文作者
论文摘要
在这里,我们通过真空封装过程报告了新的可能的磁性绝缘体(MTI)Febi2Te4的成功单晶生长。粉末XRD数据的详细rietveld分析显示,AS成长的MTI晶体主要由Febi2Te4相控制,以及BI2TE3和FETE的少数阶段。扫描电子显微镜(SEM)图像显示了AS成长的MTI单晶的形态,为分层型层状结构。晶体的拉曼光谱法在65、110和132 cm-1处表现出三种不同的声子模式,以及在90和144厘米1处的两个分裂次级模式。次级拆分模式是BI2TE3单位电池中FETE插入的结果。磁力抗性测量已在不同的温度下进行,即在高达12个特斯拉的施加磁场中,在200K,20K和2K中进行了耐磁性测量,与纯BI2TE3晶体相比,MR非常低。 DC磁化测量值的温度依赖性表明,Febi2Te4晶体主要是超过295 K以上的铁磁(FM)或Ferri-Magnetic性质,尽管在54-46K时也可以看到次级弱磁过渡。详细的等温磁化(MH)结果表明,295K时的FM饱和矩为0.00213EMU/G,几乎是不变的,直到400K。总结,我们已经成长为MTI Febi2Te4单晶体,这可能是在室温或上方或上方或上方或上方或上方的量子构成大厅(QAH)效应的可能参与者。
Here we report successful single crystal growth of new possible magnetic topological insulator (MTI) FeBi2Te4 by self-flux method via vacuum encapsulation process. The detailed Rietveld analysis of Powder XRD data shows the as grown MTI crystal to be mainly dominated by FeBi2Te4 phase along with minority phases of Bi2Te3 and FeTe. Scanning electron microscope (SEM) image shows the morphology of as grown MTI single crystal to be of layered type laminar structure. Raman spectroscopy of the crystal exhibited three distinct phonon modes at 65, 110, and 132 cm-1 along with two split secondary modes at 90, and 144cm-1. The secondary split modes are result of FeTe intercalation in Bi2Te3 unit cell. Magneto-resistance measurement has been performed at different temperatures i.e. 200K, 20K and 2K in applied magnetic fields up to 12 Tesla, which showed very low MR in comparison to pure Bi2Te3 crystal. Temperature dependence of DC magnetization measurements show the FeBi2Te4 crystal to be mainly of ferromagnetic (FM) or ferri-magnetic nature above 295 K, albeit a secondary weak magnetic transition is seen at 54-46K as well. Detailed isothermal magnetization (MH) results showed that FM saturation moment at 295K is 0.00213emu/g, which is nearly invariant till 400 K. Summary, we had grown an MTI FeBi2Te4 single crystal, which may be a possible entrant for Quantum Anomalous Hall (QAH) effect at room temperature or above.