Degenerate Topological Edge States in Multimer Chains

Abstract

We propose and experimentally realize a class of quasi-one-dimensional topological lattices whose unit cells are constructed by coupled multiple identical resonators, with uniform hopping and inversion symmetry. In the presence of path-induced effective zero hopping within the unit cells, the systems are characterized by complete multimerization with degenerate $-1$ energy edge states for open boundary condition. Su-Schrieffer-Heeger subspaces with fully dimerized limits corresponding to pairs of nontrivial flat bands are derived from the Hilbert spaces. In particular, topological bound states in the continuum (BICs) are inherently present in even multimer chains, manifested by embedding the topological bound states into a continuous band assured by bulk-boundary correspondence. Moreover, we experimentally demonstrate the degenerate topological edge states and topological BICs in inductor-capacitor circuits.

arXiv comment6page,4figures

References in corpus (38)

• Topological Insulators
• Topological insulators and superconductors
• Topological Photonics
• Topological Photonics
• Classification of topological quantum matter with symmetries
• Edge states and topological invariants of non-Hermitian systems
• Exceptional Topology of Non-Hermitian Systems
• Colloquium: Topological Band Theory
• Symmetry and Topology in Non-Hermitian Physics
• Topological Acoustics
• Topological Origin of Non-Hermitian Skin Effects
• Light-induced gauge fields for ultracold atoms
• Anomalous edge state in a non-Hermitian lattice
• Topological Bands for Ultracold Atoms
• Observation of bulk boundary correspondence breakdown in topolectrical circuits
• Zoo of quantum-topological phases of matter
• Topolectrical circuits
• Non-Hermitian Topological Invariants in Real Space
• Time Reversal Invariant Topologically Insulating Circuits
• Topological properties of linear circuit lattices
• Photonic Topological Insulating Phase Induced Solely by Gain and Loss
• Higher-order topological corner states induced by gain and loss
• Topological Quantum Optics in Two-Dimensional Atomic Arrays
• Coexistence of quantized and non-quantized geometric phases in quasi-one-dimensional systems without inversion symmetry
• Topological defect engineering and PT-symmetry in non-Hermitian electrical circuits
• Edge states in trimer lattices
• Non-Hermitian Dirac Cones
• Experimentally Detecting Quantized Zak Phases without Chiral Symmetry in Photonic Lattices
• Realizing a dynamical topological phase in a trapped-ion quantum simulator
• Coherent control of quantum topological states of light in Fock-state lattices
• Topological quantum states of matter in iron-based superconductors: From concepts to material realization
• Topologically Protected Quantum Coherence in a Superatom
• Topological phases of quantized light
• Dissipative Topological Phase Transition with Strong System-Environment Coupling
• Floquet topological phase transitions in a periodically quenched dimer
• Always-Real-Eigenvalued Non-Hermitian Topological Systems
• Wannier Function Methods for Topological Modes in 1D Photonic Crystals
• Topological transitions in dissipatively coupled Su-Schrieffer-Heeger models