Aharonov-Bohm interference and phase-coherent surface-state transport in topological insulator rings

Abstract

We present low-temperature magnetotransport measurements on selectively-grown Sb${}_2$Te${}_3$-based topological insulator ring structures. These topological insulator ring geometries display clear Aharonov-Bohm oscillations in the conductance originating from phase-coherent transport around the ring. The temperature dependence of the oscillation amplitude indicates that the Aharonov-Bohm oscillations originate from ballistic transport along the ring arms. The oscillations can therefore be attributed to topological surface states, which can maintain a quasi-ballistic transport regime in the presence of disorder. Further insight on the phase coherence is gained by comparing with similar Aharonov-Bohm-type oscillations in topological insulator nanoribbons exposed to an axial magnetic field. Here, quasi-ballistic phase-coherent transport is confirmed for closed-loop topological surface states in transverse direction enclosing the cross-section of the nanoribbon. In contrast, the appearance of universal conductance fluctuations indicates phase-coherent transport in the diffuse regime, which is attributed to bulk carrier transport. Thus, it appears that even in the presence of diffusive $p$-type charge carriers in Aharonov-Bohm ring structures, phase-coherent quasi-ballistic transport of topologically protected surface states is maintained over long distances.

arXiv comment11 pages (including Supplementary Material), 5 figures, 4 supplementary figures

References in corpus (21)

• Topological Insulators
• Topological insulators and superconductors
• Non-Abelian Anyons and Topological Quantum Computation
• Kwant: a software package for quantum transport
• Quantum Transport in Semiconductor Nanostructures
• Majorana Zero Modes and Topological Quantum Computation
• Aharonov-Bohm interference in topological insulator nanoribbons
• Milestones toward Majorana-based quantum computing
• Flux-controlled quantum computation with Majorana fermions
• Controlling bulk conductivity in topological insulators: Key role of anti-site defects
• Two-dimensional surface charge transport in topological insulators
• Aharonov-Bohm Oscillations in a Quasi-Ballistic 3D Topological Insulator Nanowire
• Mesoscopic decoherence in Aharonov-Bohm rings
• Charge fluctuation induced dephasing in a gated mesoscopic interferometer
• Quasi-ballistic transport of Dirac fermions in a Bi2Se3 nanowire
• Probing Spin Helical Surface States in Topological HgTe Nanowires
• Enhanced transport length of spin-helical Dirac fermions in disordered 3D topological insulators
• Quantum transport in topological surface states of Bi${}_2$Te${}_3$ nanoribbons
• Magnetotransport signatures of three-dimensional topological insulator nanostructures
• Adjustable quantum interference oscillations in Sb-doped Bi2Se3 topological insulator nanoribbons
• Suppression of scattering in quantum confined 2D-helical Dirac systems

Cited by in corpus (6)

• Transport response of topological hinge modes in $\alpha$-Bi${}_4$Br${}_4$
• Thermal junctions controlled with Aharonov-Bohm phases
• Quantum Coherent Transport of 1D ballistic states in second order topological insulator Bi${}_4$Br${}_4$
• Selective-Area Epitaxy of Bulk-Insulating (Bi${}_x$Sb${}_{1-x}$)${}_2$Te${}_3$ Films and Nanowires by Molecular Beam Epitaxy
• In-plane magnetic field driven conductance modulations in topological insulator kinks
• Hearing the shape of a Dirac drum: Dual quantum Hall states on curved surfaces