Department of Physics and Engineering Physics, Tulane University, New Orleans, LA 70118, USA.
J Phys Condens Matter. 2014 Mar 5;26(9):095801. doi: 10.1088/0953-8984/26/9/095801. Epub 2014 Feb 12.
We have studied the effect of spin-orbital coupling (SOC) on the electronic transport properties of the thermoelectric material β-K₂Bi₈Se₁₃ via magnetoresistance measurements. We found that the strong SOC in this material results in the weak antilocalization (WAL) effect, which can be described well by a three-dimensional weak localization model. The phase coherence length extracted from theoretical fitting exhibits a power-law temperature dependence, with an exponent around 2.1, indicating that the electron dephasing is governed by electron-transverse phonon interactions. As in topological insulators, the WAL effect in β-K₂Bi₈Se₁₃ can be quenched by magnetic impurities (Mn) but is robust against non-magnetic impurities (Te). Although our magnetotransport studies provide no evidence for topological surface states, our analyses suggest that SOC plays an important role in determining the thermoelectric properties of β-K₂Bi₈Se₁₃.
我们通过磁阻测量研究了自旋轨道耦合（SOC）对热电器件β-K₂Bi₈Se₁₃电子输运性质的影响。我们发现，该材料中的强 SOC 导致了弱反局域（WAL）效应，这可以用三维弱局域模型很好地描述。从理论拟合中提取的相位相干长度表现出幂律温度依赖性，指数约为 2.1，表明电子退相干由电子-横向声子相互作用控制。与拓扑绝缘体一样，β-K₂Bi₈Se₁₃中的 WAL 效应可以被磁性杂质（Mn）猝灭，但对非磁性杂质（Te）具有鲁棒性。尽管我们的磁输运研究没有提供拓扑表面态的证据，但我们的分析表明，SOC 在决定β-K₂Bi₈Se₁₃的热电性质方面起着重要作用。
