论文标题
磁场依赖性电阻跨界和对数与拓扑绝缘体中的非饱和磁倍率
Magnetic field-dependent resistance crossover and logarithmic to non-saturating magnetoresistance in topological insulator Bi$_2$Te$_3$
论文作者
论文摘要
我们报告了一个金属 - 绝缘体，例如在有230k的温度下，在存在正常表面的外部磁场的情况下，在230K的温度下，单晶3D拓扑绝缘子BI2TE3中的过渡。在较大的磁场强度下，这种过渡变得更加突出，残留电阻值随磁场线性增加。在低温下，磁场的磁场依赖性显示从对数到线性行为的过渡，并且该过渡的起始磁场值随温度的升高而降低。对数磁化率表明表面狄拉克电子的抗本地化弱，而高温行为由于内在杂质而起源于散装载体。在〜230 K以上的较高温度下，观察到完全古典的Lorentz模型型二次行为。我们还表明，在磁铁传输特性中，实验观察到的在〜230K处的异常并非源自BI2TE3中的任何堆叠断层。
We report a metal-insulator like transition in single crystalline 3D topological insulator Bi2Te3 at a temperature of 230K in presence of an external magnetic field applied normal to the surface. This transition becomes more prominent at larger magnetic field strength with the residual resistance value increasing linearly with the magnetic field. At low temperature, the magnetic field dependence of the magnetoresistance shows a transition from logarithmic to linear behavior and the onset magnetic field value for this transition decreases with increasing temperature. The logarithmic magnetoresistance indicates the weak anti-localization of the surface Dirac electrons while the high temperature behavior originates from the bulk carriers due to intrinsic impurities. At even higher temperatures beyond~230 K, a completely classical Lorentz model type quadratic behavior of the magnetoresistance is observed. We also show that the experimentally observed anomalies at ~230K in the magneto-transport properties do not originate from any stacking fault in Bi2Te3.
