Topological Insulator Magnetic Tunnel Junctions: Quantum Hall Effect and Fractional Charge via Folding

Abstract

We provide a characterization of tunneling between coupled topological insulators in 2D and 3D under the influence of a ferromagnetic layer. We explore conditions for such systems to exhibit integer quantum Hall physics and localized fractional charge, also taking into account interaction effects for the 2D case. We show that the effects of tunneling are topologically equivalent to a certain deformation or folding of the sample geometry. Our key advance is the realization that the quantum Hall or fractional charge physics can appear in the presence of only a \emph{single} magnet unlike previous proposals which involve magnetic domain walls on the surface or edges of topological insulators respectively. We give illustrative topological folding arguments to prove our results and show that for the 2D case our results are robust even in the presence of interactions.

5 pages, 2 figures

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Cited by in corpus (15)

• Surface State Magnetization and Chiral Edge States on Topological Insulators
• Coulomb blockade microscopy of spin density oscillations and fractional charge in quantum spin Hall dots
• Edge states of a three-dimensional topological insulator
• Spin Transfer Torque and Electric Current in Helical Edge States in Quantum Spin Hall Devices
• Spin textures of strongly correlated spin Hall quantum dots
• Correlation functions for the detection of Wigner molecules in a one-channel Luttinger liquid quantum dot
• Observation of chiral currents at the magnetic domain boundary of a topological insulator
• Electric coupling in scanning SQUID measurements
• Demonstration of Dissipative Quasihelical Edge Transport in Quantum Anomalous Hall Insulators
• Magnetic AC control of the spin textures in a helical Luttinger liquid
• Nonlinear Magneto-Optical and Magnetoelectric Phenomena in Topological Insulator Heterostructures
• Confining electrons on a topological insulator surface using potentials and a magnetic field
• Parity dependent Josephson current through a helical Luttinger liquid
• Edge bands and vertical transport in topological insulator/magnetic insulator heterostructures
• Weak localization effect in topological insulator micro flakes grown on insulating ferrimagnet BaFe12O19