Transport Induced Dimer State from Topological Corner States

Abstract

Recently, a new type of second-order topological insulator has been theoretically proposed by introducing an in-plane Zeeman field into the Kane-Mele model in the two-dimensional honeycomb lattice. A pair of topological corner states arise at the corners with obtuse angles of an isolated diamond-shaped flake. To probe the corner states, we study their transport properties by attaching two leads to the system. Dressed by incoming electrons, the dynamic corner state is very different from its static counterpart. Resonant tunneling through the dressed corner state can occur by tuning the in-plane Zeeman field. At the resonance, the pair of spatially well separated and highly localized corner states can form a dimer state, whose wavefunction extends almost the entire bulk of the diamond-shaped flake. By varying the Zeeman field strength, multiple resonant tunneling events are mediated by the same dimer state. This re-entrance effect can be understood by a simple model. These findings extend our understanding of dynamic aspects of the second-order topological corner states.

5 pages, 4 figures for the main text. SM attached

References in corpus (15)

• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantized Anomalous Hall Effect in Magnetic Topological Insulators
• Topological Crystalline 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
• Nonlocal edge state transport in the quantum spin Hall state
• Higher-order topological insulators and semimetals on the breathing Kagome and pyrochlore lattices
• Quantum Anomalous Hall Effect in Graphene from Rashba and Exchange Effects
• Topological confinement in bilayer graphene
• Electronic Highways in Bilayer Graphene
• Valley-Hall Kink and Edge States in Multilayer Graphene
• Current partition at zero-line intersection of quantum anomalous Hall topologies
• Zero-line modes at stacking faulted domain walls in multilayer graphene
• Analytical solutions of the two-dimensional Dirac equation for a topological channel intersection

Cited by in corpus (2)

• Anti-chiral edge states and hinge states based on the Haldane model
• Transport features of topological corner states in honeycomb lattice with multihollow structure