论文标题
钒掺杂bi $ _ {2} $ te $ _ {2.4} $ se $ _ {0.6} $散装拓扑绝缘子
Low-temperature magnetoresistance hysteresis in Vanadium-doped Bi$_{2}$Te$_{2.4}$Se$_{0.6}$ bulk topological insulators
论文作者
论文摘要
bi $ _ {2} $ te $ _ {2.4} $ se $ _ {0.6} $单晶显示无缝隙拓扑表面状态和掺杂（$ x $）的钒，可以在散装带隙中移动化学势。因此，电阻率，载体密度和迁移率在10 K以下恒定，并且磁势显示出弱的抗静电性，如所预期的低温转运性能所预期的，以所谓的三维拓扑“绝缘子”为主导的无间隙表面状态。然而，磁路阻塞还显示出滞后，具体取决于扫描速率和磁场方向。在这里，我们提供的证据表明，如果三维体积状态和准三维拓扑状态都会有助于运输（$ x $ = 0和0.03），则这种磁静力滞后会得到增强，并且如果拓扑状态统治运输（$ x $ = 0.015），则大多会被抑制。根据不同可用状态之间的自旋依赖散射讨论结果
Bi$_{2}$Te$_{2.4}$Se$_{0.6}$ single crystals show gapless topological surface states and doping ($x$) with Vanadium allows to shift the chemical potential in the bulk band gap. Accordingly, the resistivity, carrier density, and mobility are constant below 10 K and the magnetoresistance shows weak antilocalization as expected for low-temperature transport properties dominated by gapless surface states of so-called three-dimensional topological "insulators". However, the magnetoresistance also shows a hysteresis depending on the sweep rate and the magnetic field direction. Here, we provide evidence that such magnetoresistance hysteresis is enhanced if both three-dimensional bulk states and quasi-two-dimensional topological states contribute to the transport ($x$ = 0 and 0.03), and it is mostly suppressed if the topological states govern transport ($x$ = 0.015). The results are discussed in terms of spin-dependent scattering between the different available states
