Coherent Oscillations and Giant Edge Magnetoresistance in Singly Connected Topological Insulators

Abstract

The topological insulators have a gap in the bulk but extended states at the edge that can carry current. We study a geometry in which such edge states will manifest themselves through periodic oscillations in the magnetoconductance of a singly connected sample coupled to leads through narrow point contacts. The oscillations occur due to quantum interference of helical edge states of electrons traveling along the circumference of the sample, and have a period of B_0=h/eA_{eff}, where A_{eff} is the effective area enclosed by the edge states of the sample. Our calculation indicates the possibility of a large change in the magnetoresistance at small B, termed giant edge magnetoresistance, which can have potential for application. The zero field conductance also exhibits oscillations as a function of the Fermi energy due to interference between edge states. The amplitude of the oscillations is governed by, and therefore can be used to investigate, the transverse width of the edge channels.

4 pages, 5 figures

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Cited by in corpus (20)

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• Well-localized edge states in two-dimensional topological insulators: ultrathin Bi films
• Numerical study of the topological Anderson insulator in HgTe/CdTe quantum wells
• Two-dimensional surface charge transport in topological insulators
• Bound states and persistent currents in topological insulator rings
• Detecting Majorana bound states
• Multi-critical Behavior in Topological Phase Transitions
• Devices with electrically tunable topological insulating phases
• Generating and controlling spin-polarized currents induced by a quantum spin Hall antidot
• Nonlinear spin-thermoelectric transport in two-dimensional topological insulators
• Dephasing of spin and charge interference in helical Luttinger liquids
• Multi-critical topological transition at quantum criticality
• Robust topological insulator surface conduction under strong surface disorder
• Point contacts and localization in generic helical liquids
• Coherent spin transport through helical edge states of topological insulator
• Spin and charge transport through helical Aharonov-Bohm interferometer with strong magnetic impurity
• Tunneling Aharonov-Bohm interferometer on helical edge states
• Aharonov-Bohm effect in a helical ring with long-range hopping: Effects of Rashba spin-orbit interaction and disorder
• Transport through a quantum spin Hall antidot as a spectroscopic probe of spin textures
• Enhanced and stable spin Hall conductivity in a disordered time-reversal and inversion symmetry broken topological insulator thin film