Super-resonant transport of topological surface states subjected to in-plane magnetic fields

Abstract

Magnetic oscillations of Dirac surface states of topological insulators are expected to be associated with the formation of Landau levels or the Aharonov-Bohm effect. We instead study the conductance of Dirac surface states subjected to an in-plane magnetic field in presence of a barrier potential. Strikingly, we find that, in the case of large barrier potentials, the surface states exhibit pronounced oscillations in the conductance when varying the magnetic field, in the \textit{absence} of Landau levels or the Aharonov-Bohm effect. These novel magnetic oscillations are attributed to the emergence of \textit{super-resonant regimes} by tuning the magnetic field, in which almost all propagating electrons cross the barrier with perfect transmission. In the case of small and moderate barrier potentials, we also identify a positive magnetoconductance which is due to the increase of the Fermi surface by tilting the surface Dirac cone. Moreover, we show that for weak magnetic fields, the conductance displays a shifted sinusoidal dependence on the field direction with period $\pi$ and phase shift determined by the tilting direction with respect to the field direction. Our predictions can be applied to many topological insulators, such as HgTe and Bi${}_2$Se${}_3$, and provide important insights into exploring and understanding exotic magnetotransport properties of topological surface states.

5+2 pages, 4 figures

References in corpus (20)

• Topological Insulators with Inversion Symmetry
• Chiral tunneling and the Klein paradox in graphene
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• A topological Dirac insulator in a quantum spin Hall phase : Experimental observation of first strong topological insulator
• The Quantum Spin Hall Effect: Theory and Experiment
• Gate-Voltage Control of Chemical Potential and Weak Anti-localization in Bismuth Selenide
• Two-dimensional Dirac fermions in a topological insulator: transport in the quantum limit
• Topological origin of subgap conductance in insulating bilayer graphene
• Impurity effect on weak anti-localization in the topological insulator Bi2Te3
• Observation of topological surface state quantum Hall effect in an intrinsic three-dimensional topological insulator
• Direct Evidence for the Dirac-Cone Topological Surface States in Ternary Chalcogenide TlBiSe2
• Aharonov-Bohm oscillations in disordered topological insulator nanowires
• Quantum Hall Effect on Top and Bottom Surface States of Topological Insulator (Bi1-xSbx)2Te3 Films
• Quantum interference and Aharonov-Bohm oscillations in topological insulators
• Anomalous Aharonov-Bohm conductance oscillations from topological insulator surface states
• Weak Localization and Antilocalization in Topological Insulator Thin Films with Coherent Bulk-Surface Coupling
• Anisotropic and strong negative magneto-resistance in the three-dimensional topological insulator Bi2Se3
• Imaging two-component nature of Dirac-Landau levels in the topological surface state of Bi2Se3
• Ab initio study of topological surface states of strained HgTe
• Directional electron-filtering at a superconductor-semiconductor interface