122 citations · 1.1k across the 47 of their papers we have counts for
11 papers · 1 filter
Equireflectionality and customized unbalanced coherent perfect absorption in asymmetric waveguide networks
Malte Röntgen, Olivier Richoux, Georgios Theocharis +4
We explore the scattering of waves in designed asymmetric one-dimensional waveguide networks. We show that the reflection between two ports of an asymmetric network can be identica…
Subwavelength Su-Schrieffer-Heeger topological modes in acoustic waveguides
Antonin Coutant, Vassos Achilleos, Olivier Richoux +2
Topological systems furnish a powerful way of localizing wave energy at edges of a structured material. Usually this relies on Bragg scattering to obtain bandgaps with nontrivial t…
Multi-functional resonant acoustic networks for wave routing
Olivier Richoux, Vassos Achilleos, Georgios Theocharis +2
We demonstrate that asymmetric 3-port devices can be used to design a multi-functional set-up operating as a symmetric combiner and splitter at the same frequency. For a concrete i…
Observation of edge waves in a two-dimensional Su-Schrieffer-Heeger acoustic network
Li-Yang Zheng, Vassos Achilleos, Olivier Richoux +2
In this work, we experimentally report the acoustic realization the two-dimensional (2D) Su-Schrieffer-Heeger (SSH) model in a simple network of air channels. We analytically study…
Subwavelength Interferometric Control of Absorption in Three-port Acoustic Network
O. Richoux, V. Achilleos, G. Theocharis +1
Utilizing the effect of losses, we show that symmetric 3-port devices exhibit coherent perfect absorption of waves and we provide the corresponding conditions on the reflection and…
Non-Hermitian Acoustic Metamaterials: the role of Exceptional Points in sound absorption
V. Achilleos, G. Theocharis, O. Richoux +1
Effective non-Hermitian Hamiltonians are obtained to describe coherent perfect absorbing and lasing boundary conditions. PT -symmetry of the Hamiltonians enables to design configur…
Coherent Perfect Absorption induced by the nonlinearity of a Helmholtz resonator
V. Achilleos, O. Richoux, G. Theocharis
In this work, we analytically report Coherent Perfect Absorption induced by the acoustic nonlinear response of a Helmholtz Resonator side loaded to a waveguide. In particular, we s…
Control of acoustic absorption in 1D scattering by indirect coupled resonant scatterers
A. Merkel, G. Theocharis, O. Richoux +2
We experimentally report perfect acoustic absorption through the interplay of the inherent losses and transparent modes with high factor. These modes are generated in a two-por…
Invariant currents in lossy acoustic waveguides with complete local symmetry
P. A. Kalozoumis, O. Richoux, F. K. Diakonos +2
We implement the concept of complete local symmetry in lossy acoustic waveguides. Despite the presence of losses, the existence of a spatially invariant current is shown theoretica…
Nonlinear Hysteretic Torsional Waves
J. Cabaret, P. Béquin, G. Theocharis +3
We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads.…
Perfect and broadband acoustic absorption by critical coupling
V. Romero-García, G. Theocharis, O. Richoux +3
We experimentally and analytically report broadband and narrowband perfect absorption in two different acoustic waveguide-resonator geometries by the mechanism of critical coupling…