Magnetic-flux tunable electronic transport through domain walls in a three-dimensional second-order topological insulator

Abstract

The three-dimensional (3D) topological insulators (TIs), hosting topologically protected helical surface states, can be promoted into second-order TIs when a diagonal Zeeman term, typical of magnetic doping, is introduced. The latter hosts exotic chiral one-dimensional (1D) topological hinge states (THSs). In this paper, we investigate the electronic transport of THSs through a magnetic domain wall (DW) in a 3D TI nanowire. Due to the sign reversal of the out-of-plane magnetization across the DW, four 1D topological boundary states, residing on the edge of the DW, arise and form an enclosed loop mediating the counterpropagating THSs. By applying a uniform magnetic field parallel to the nanowire, we obtain a perfect sinusoidal Aharonov-Bohm oscillation in the two-terminal conductance $G$, formulated by $G=\frac{e^2}{2h}\left[1-\cos (\pi \Phi /{\Phi }_0)\right]$, with $\Phi$ the magnetic flux through the DW and ${\Phi }_0=h/2e$ the flux quantum. Applying a phenomenological scattering matrix approach, we explain this novel Aharonov-Bohm oscillation perfectly, and attribute the constructive (destructive) interference of transmission at $\Phi ={\Phi }_0$ (0) to the $\pi$-spin rotation of the THSs traveling through the DW. Extending our study to a double-DW junction, where the central region has antiparallel magnetization to the leads, we observe Fabry-P{é}rot oscillations, in which the conductance minima are tuned by the magnetic flux. Our findings open a new avenue for finely controlling the quantum transport of THSs in magnetic systems using magnetic flux, and provide a faithful way for detecting THSs in experiments.

References in corpus (19)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Electric Multipole Moments, Topological Multipole Moment Pumping, and Chiral Hinge States in Crystalline Insulators
• $(d-2)$-dimensional edge states of rotation symmetry protected topological states
• Reflection symmetric second-order topological insulators and superconductors
• Quantum Anomalous Hall Effect in Hg${}_{1-y}$Mn${}_y$Te Quantum Wells
• The development of ferromagnetism in the doped topological insulator Bi2-xMnxTe3
• Precise quantization of anomalous Hall effect near zero magnetic field
• Disorder-induced enhancement of transport through graphene p-n junctions
• Layer Hall effect induced by hidden Berry curvature in antiferromagnetic insulators
• Higher-order Fabry-Pérot Interferometer from Topological Hinge States
• Magnetic topological transistor exploiting layer-selective transport
• Third-order topological insulator in three-dimensional lattice of magnetic vortices
• Second-order topology and supersymmetry in two-dimensional topological insulators
• Hinge States of Second-Order Topological Insulators as a Mach-Zehnder Interferometer
• Realization of a three-dimensional quantum Hall effect in a Zeeman-induced second order topological insulator on a torus
• Conductance oscillations of antiferromagnetic layer tunnel junctions