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arXiv · 1707.09530

Effect of chiral selective tunneling on quantum transport in magnetic topological-insulator thin films

Taahere Sabze·Hosein Cheraghchi
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Abstract

The electronic transport properties in magnetically doped ultra-thin films of topological-insulators is investigated by using Landauer-buttiker formalism. The chiral selective tunneling is addressed in such systems which leads to transport gap and as a consequence current blocking. This quantum blocking of transport occurs when the magnetic states with opposite chirality are aligned energetically. This can be obsereved when an electron tunnels through a barrier or well of magnetic potential induced by the exchange field. It is proved and demonstrated that this chiral transition rule fails when structural inversion asymmetric potential or an in-plane magnetization is turning on. This new finding is useful to interpret quantum transport through topological-insulator thin films especially to shed light on longitudinal conductance behavior of quantum anomalous Hall effect. Besides, one can design electronic devices by means of magnetic topological-insulator thin films based on the chiral selective tunneling leading to negative differential resistance.

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Taahere Sabze, Hosein Cheraghchi. 2017-07-29. Effect of chiral selective tunneling on quantum transport in magnetic topological-insulator thin films. https://doi.org/10.1103/physrevb.96.155440

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