Department of Physics, University of California at Berkeley, Berkeley, California 94720, USA.
Phys Rev Lett. 2010 Nov 12;105(20):206601. doi: 10.1103/PhysRevLett.105.206601. Epub 2010 Nov 11.
We study Aharonov-Bohm (AB) conductance oscillations arising from the surface states of a topological insulator nanowire, when a magnetic field is applied along its length. With strong surface disorder, these oscillations are predicted to have a component with anomalous period Φ(0)=hc/e, twice the conventional period. The conductance maxima are achieved at odd multiples of 1/2Φ(0), implying that a π AB phase for electrons strengthens the metallic nature of surface states. This effect is special to topological insulators, and serves as a defining transport property. A key ingredient, the surface curvature induced Berry phase, is emphasized here. We discuss similarities and differences from recent experiments on Bi2Se3 nanoribbons, and optimal conditions for observing this effect.
我们研究了拓扑绝缘体纳米线表面态在磁场沿其长度方向施加时产生的阿哈罗诺夫-玻姆（AB）电导振荡。在强表面无序的情况下，这些振荡预计会有一个异常周期 Φ(0)=hc/e 的分量，是传统周期的两倍。电导最大值出现在 1/2Φ(0) 的奇数倍，这意味着电子的 AB 相位为 π 增强了表面态的金属性质。这种效应是拓扑绝缘体所特有的，是其定义性的输运性质之一。这里强调的一个关键因素是表面曲率诱导的 Berry 相。我们讨论了与最近在 Bi2Se3 纳米带的实验的异同，并讨论了观察这种效应的最佳条件。
