Identifying Axion Insulator by Quantized Magnetoelectric Effect in Antiferromagnetic ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ Tunnel Junction

Abstract

Intrinsic magnetic topological insulator ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ is believed to be an axion insulator in its antiferromagnetic ground state. However, direct identification of axion insulators remains experimentally elusive because the observed vanishing Hall resistance, while indicating the onset of the axion field, is inadequate to distinguish the system from a trivial normal insulator. Using numerical Green's functions, we theoretically demonstrate the quantized magnetoelectric current in a tunnel junction of atomically thin ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ sandwiched between two contacts, which is a smoking-gun signal that unambiguously confirms antiferromagnetic ${\mathrm{MnBi}}_2{\mathrm{Te}}_4$ to be an axion insulator. Our predictions can be verified directly by experiments.

References in corpus (9)

• Topological Field Theory of Time-Reversal Invariant Insulators
• Surface quantized anomalous Hall current and magneto-electric effect in magnetically disordered topological insulators
• Higher-order Topology of Axion Insulator EuIn${}_2$As${}_2$
• Layer Hall effect in a 2D topological Axion antiferromagnet
• Axion Electrodynamics in Topological Materials
• Electric control of a canted-antiferromagnetic Chern insulator
• Routes to realize the axion-insulator phase in MnBi${}_2$Te${}_4$(Bi${}_2$Te${}_3$)${}_n$ family: a perspective
• Critical Behavior and Universal Signature of an Axion Insulator State
• Non-local sidewall response and deviation from exact quantization of the topological magnetoelectric effect in axion-insulator thin films

Cited by in corpus (9)

• Half-Quantized Helical Hinge Currents in Axion Insulators
• Chern Number Tunable Quantum Anomalous Hall Effect in Compensated Antiferromagnets
• Electrically Controlled Anomalous Hall Effect and Orbital Magnetization in Topological Magnet MnBi2Te4
• Even-Odd Layer-Dependent Exchange Bias Effect in MnBi2Te4 Chern Insulator Devices
• High spin axion insulator
• Magnetic order-dependent giant tunneling magnetoresistance and electroresistance in van der Waals antiferromagnetic-multiferroic tunnel junctions
• Lossless Spin-Orbit Torque in Antiferromagnetic Topological Insulator MnBi${}_2$Te${}_4$
• Electrical control of intrinsic nonlinear Hall effect in antiferromagnetic topological insulator sandwiches
• Quantum interference in a superconductor-${\mathrm{MnBi}}_2{\mathrm{Te}}_4$-superconductor Josephson junction