Experimental Realization of Acoustic Chern Insulator

Abstract

Topological insulators are new states of matter in which the topological phase originates from symmetry breaking. Recently, time-reversal invariant topological insulators were demonstrated for classical wave systems, such as acoustic systems, but limited by inter-pseudo-spin or inter-valley backscattering. This challenge can be effectively overcome via breaking the time-reversal symmetry. Here, we report the first experimental realization of acoustic topological insulators with nonzero Chern numbers, viz., acoustic Chern insulator (ACI), by introducing an angular-momentum-biased resonator array with broken Lorentz reciprocity. High Q-factor resonance is leveraged to reduce the required speed of rotation. Experimental results show that the ACI featured with a stable and uniform metafluid flow bias supports one-way nonreciprocal transport of sound at the boundaries, which is topologically immune to the defect-induced scatterings. Our work opens up opportunities for exploring unique observable topological phases and developing practical nonreciprocal devices in acoustics.

arXiv comment16 pages, 4 figures

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Cited by in corpus (52)

• Topological acoustics
• Acoustic realization of quadrupole topological insulators
• Realization of an acoustic third-order topological insulator
• Band topology in classical waves: Wilson-loop approach to topological numbers and fragile topology
• Non-Hermitian route to higher-order topology in an acoustic crystal
• Roadmap on STIRAP applications
• Topological one-way large-area waveguide states in magnetic photonic crystals
• Meta-neural-network for Realtime and Passive Deep-learning-based Object Recognition
• Experimental Observation of Efficient Nonreciprocal Mode Transitions via Spatiotemporally-Modulated Acoustic Metamaterials
• Acoustic spin-Chern insulator induced by synthetic spin-orbit coupling with spin conservation breaking
• Acoustic square-root topological insulators
• Non-reciprocal sound propagation in space-time modulated media
• Floquet generation of Second Order Topological Superconductor
• Hyperbolic Topological Band Insulators
• Remote entanglement via adiabatic passage using a tunably-dissipative quantum communication system
• Half-Quantized Hall Effect and Power Law Decay of Edge Current Distribution
• Nonreciprocal phonon blockade
• Ideal type-II Weyl phase and topological transition in phononic crystals
• Demonstration of acoustic high-order Stiefel-Whitney semimetal in bilayer graphene sonic crystals
• Acoustic corner states in topological insulators with built-in Zeeman-like fields
• Topological slow light via coupling chiral edge modes with flat bands
• Topological photonic alloy
• Acoustic Metagrating Circulators: Nonreciprocal, Robust, and Tunable Manipulation with Unitary Efficiency
• Interlayer Topological Transport and Devices based on Layer Pseudospins in Photonic Valley-Hall Phases
• Abnormal topological refraction into free medium at sub-wavelength scale in valley phononic crystal plates
• Impedance responses and size-dependent resonances in topolectrical circuits via the method of images
• Edge states and corner modes in second-order topological phononic crystal plates
• Simulation of higher-order topological phases in 2D spin-phononic crystal networks
• Altermagnetism-Induced Parity Anomaly in Weak Topological Insulators
• On-chip unidirectional waveguiding for surface acoustic waves along a defect line in a triangular lattice
• Edge-following topological states
• Quasicrystalline Weyl points and dense Fermi-Bragg arcs
• Observation of squeezed Chern insulator in an acoustic fractal lattice
• Robust acoustic pulling using chiral surface waves
• Observation of Dual-band Topological Corner Modes in Acoustic Kagome Lattice with Long-range Interactions
• Chiral photon blockade in the spinning Kerr resonator
• Stacking-induced Chern insulator
• Bilayer Haldane system: Topological characterization and adiabatic passages connecting Chern phases
• Topological Classical Systems with Generalized Chiral Symmetry
• Valley and Valley-like Split-ring Topological Photonic Crystal
• All hourglass bosonic excitations in the 1651 magnetic space groups and 528 magnetic layer groups
• Symmetry-driven Phononic Metamaterials
• Family of Aperiodic Tilings with Tunable Quantum Geometric Tensor
• Hermitian and non-Hermitian topology in active matter
• Dynamics of azimuthal thermoacoustic modes in imperfectly symmetric annular geometries
• Magnetic doping-induced second-order and first-order topological phase transition inthe photonic alloy
• Low-frequency tunable topological interface states in soft phononic crystal cylinders
• Dynamical transition in non-Hermitian Chern insulator
• Experimental realization of three-dimensional elastic phononic topological insulator
• Robust zero-energy states in two-dimensional Su-Schrieffer-Heeger topological insulators
• Layer-number parity induced topological phase transition
• Semimetals without correspondence between the topological charge of nodal line/surface and Fermi arc