The General Principle behind Magnetization-induced Second-Order Topological Corner States in the Kane-Mele Model

Abstract

We propose a general principle for realizing second-order topological corner states in the modified Kane-Mele model with magnetization. It is demonstrated that the sign of the edge Dirac mass depends on the magnetization of the edge sublattice termination. By adjusting the directions of magnetization according to the type of sublattice at the termination of two edges, a mass domain wall can be induced in the presence of topological corner states at an arbitrary position. All previous work on introducing magnetization in the Kane-Mele model to realize second-order topological corner states can be explained by the presence of the Dirac mass domain wall with opposite signs. Applying this principle, we design square-shaped and armchair-type hexagon-shaped graphene nanoflakes with edge magnetization, allowing for the emergence of second-order topological corner states. Our findings serve as a general theory, demonstrating that the realization of second-order topological corner states is not limited by boundary type or nanoflake shape.

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Cited by in corpus (7)

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• Interplay of Altermagnetic Order and Wilson Mass in the Dirac Equation: Helical Edge States without Time-Reversal Symmetry
• Interlayer Coupling Induced Topological Phase Transition to Higher Order
• Two-Dimensional Higher-Order Topological Metals
• Quantum spin Hall effect in bilayer honeycomb lattices with C-type antiferromagnetic order
• Engineering Two-Dimensional Hybrid-Order Topological Insulators via Trilayer Coupling
• Second-order topological insulator induced by compensated altermagnetism without bulk spin splitting