Spontaneously-Induced Dirac Boundary State and Digitization in a Nonlinear Resonator Chain
arXiv:2204.03746 · doi:10.1103/PhysRevLett.129.135501
Abstract
The low-energy excitations in many condensed matter and metamaterial systems can be well described by the Dirac equation. The mass term associated with these collective excitations, also known as the Dirac mass, can take any value and is directly responsible for determining whether the resultant band structure exhibits a band gap or a Dirac point with linear dispersion. Manipulation of this Dirac mass has inspired new methods of band structure engineering and electron confinement. Notably, it has been shown that a massless state necessarily localizes at any domain wall that divides regions with Dirac masses of different signs. These localized states are known as Jackiw-Rebbi-type (JR-type) Dirac boundary modes and their tunability and localization features have valuable technological potential. In this study, we experimentally demonstrate that nonlinearity within a 1D Dirac material can result in the spontaneous appearance of a domain boundary for the Dirac mass. Our experiments are performed in a dimerized magneto-mechanical metamaterial that allows complete control of both the magnitude and sign of the local material nonlinearity, as well as the sign of the Dirac mass. We find that the massless bound state that emerges at the spontaneously appearing domain boundary acts similarly to a dopant site within an insulator, causing the material to exhibit a dramatic binary switch in its conductivity when driven above an excitation threshold.
References in corpus (30)
- The electronic properties of graphene
- Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
- Quantum Spin Hall Insulator State in HgTe Quantum Wells
- Massive Dirac fermions and Hofstadter butterfly in a van der Waals heterostructure
- Substrate-induced bandgap in graphene on hexagonal boron nitride
- Cloning of Dirac fermions in graphene superlattices
- Dirac materials
- Surface Impedance and Bulk Band Geometric Phases in One-Dimensional Systems
- Edge states in Graphene: from gapped flat band to gapless chiral modes
- Edge waves in plates with resonators: An elastic analogue of the quantum valley Hall effect
- Ballistic Josephson junctions in edge-contacted graphene
- Domain walls in gapped graphene
- Band topology in classical waves: Wilson-loop approach to topological numbers and fragile topology
- Manipulation of Dirac Cones in Mechanical Graphene
- Magnon Dirac materials
- Unexpected edge conduction in HgTe quantum wells under broken time reversal symmetry
- Edge Transport in the Trivial Phase of InAs/GaSb
- Photonic analogue of Zitterbewegung in binary waveguide arrays
- Experimentally Detecting Quantized Zak Phases without Chiral Symmetry in Photonic Lattices
- Demonstrating an in-situ topological band transition in cylindrical granular chains
- Photonic simulation of topological excitations in metamaterials
- Optical analogue of relativistic Dirac solitons in binary waveguide arrays
- Stability of topological edge states under strong nonlinear effects
- Photonic Jackiw-Rebbi states in all-dielectric structures controlled by bianisotropy
- Trapped state at a dislocation in a weak magnetomechanical topological insulator
- Linear and nonlinear photonic Jackiw-Rebbi states in waveguide arrays
- Granular Superconductor in a honeycomb lattice as a realization of Bosonic Dirac Material
- Probing the topological properties of the Jackiw-Rebbi model with light
- Robustness and Universality of Surface States in Dirac Materials
- Photonic band-gap properties for two-component slow light