Topological transitions induced by antiferromagnetism in a thin-film topological insulator

Abstract

Ferromagnetism in topological insulators (TIs) opens a topologically non-trivial exchange band gap, providing an exciting platform to manipulate the topological order through an external magnetic field. Here, we experimentally show that the surface of an antiferromagnetic thin film can independently control the topological order of the top and the bottom surface states of a TI thin film through proximity couplings. During the magnetization reversal in a field scan, two intermediate spin configurations stem from unsynchronized magnetic switchings of the top and the bottom AFM/TI interfaces. These magnetic configurations are shown to result in new topological phases with non-zero Chern numbers for each surface, introducing two counter-propagating chiral edge modes inside the exchange gap. This change in the number of transport channels, as the result of the topological transitions, induces antisymmetric magneto-resistance spikes during the magnetization reversal. With the high Neel ordering temperature provided by the antiferromagnetic layers, the signature of the induced topological transition persists in transport measurements up to a temperature of around 90 K, a factor of three over the Curie temperature in a typical magnetically doped TI thin film.

References in corpus (20)

• Topological insulators and superconductors
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• $Z_2$ Topological Order and the Quantum Spin Hall Effect
• Berry Phase Effects on Electronic Properties
• Anomalous Hall effect
• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• Antiferromagnetic spintronics
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• High-precision realization of robust quantum anomalous Hall state in a hard ferromagnetic topological insulator
• Scale-Invariant Dissipationless Chiral Transport in Magnetic Topological Insulators beyond the Two-Dimensional Limit
• Massive Dirac fermions and spin physics in an ultrathin film of topological insulator
• Chiral Topological Superconductor From the Quantum Hall State
• Effective continuous model for surface states and thin films of three dimensional topological insulators
• Realization of the Axion Insulator State in Quantum Anomalous Hall Sandwich Heterostructures
• Tailoring tricolor structure of magnetic topological insulator for robust axion insulator
• Tailoring Exchange Couplings in Magnetic Topological Insulator/Antiferromagnet Heterostructures
• Massive Dirac surface states in topological insulator/magnetic insulator heterostructures
• Independent tuning of electronic properties and induced ferromagnetism in topological insulators with heterostructure approach
• Antisymmetric magnetoresistance in magnetic multilayers with perpendicular anisotropy
• Quantum Transport in Magnetic Topological Insulator Thin Films

Cited by in corpus (19)

• Antisymmetric magnetoresistance in van der Waals Fe3GeTe2/graphite/Fe3GeTe2 tri-layer heterostructures
• Record-High Proximity-Induced Anomalous Hall Effect in (Bi${}_x$Sb${}_{1-x}$)2Te${}_3$ Thin Film Grown on CrGeTe${}_3$ Substrate
• Tailoring Hybrid Anomalous Hall Response in Engineered Magnetic Topological Insulator Heterostructures
• Effects of filling, strain, and electric field on the Néel vector in antiferromagnetic CrSb
• Realization of the Chern insulator and Axion insulator phases in antiferromagnetic $MnTe$-$B{i}_2(Se,Te{)}_3$-$MnTe$ heterostructures
• Elucidating proximity magnetism through polarized neutron reflectometry and machine learning
• Non-local sidewall response and deviation from exact quantization of the topological magnetoelectric effect in axion-insulator thin films
• Finite-size Topology
• Non-equilibrium spin density and spin-orbit torque in three dimensional topological insulators - antiferromagnet heterostructure
• Modulation of anisotropic magnetoresistance by anomalous Hall signal and its application to real-time domain wall velocity measurement
• Electrically Tunable Wafer-Sized Three-Dimensional Topological Insulator Thin Films Grown by Magnetron Sputtering
• Electron transport through antiferromagnetic spin textures and skyrmions in a magnetic tunnel junction
• Topological antiferromagnetic spintronics: Part of a collection of reviews on antiferromagnetic spintronics
• Universally optimizable strategy for magnetic gaps towards high-temperature quantum anomalous Hall states via magnetic-insulator/topological-insulator building-blocks
• Topological Insulators-Based Magnetic Heterostructure
• From classical to quantum regime of topological surface states via defect engineering
• Single-crystalline CrSb(0001) thin films grown by dc magnetron co-sputtering
• Non-reciprocal magnetoresistance, directional inhomogeneity and mixed symmetry Hall devices
• Emergent topology in thin films of nodal line semimetals