Publications associées à Development of Leaky-Wave Antenna Applications with Acoustics Metamaterials: from the Acoustic Dispersive Prism to Sound Direction Finding with a Single Microphone

Publications associées (26)

Engineering quasi-bound states in the continuum in asymmetric waveguide gratings

The occurrence of quasi-bound states in the continuum (qBIC) in all-dielectric asymmetric grating waveguide couplers with different degrees of asymmetry under normal light incidence is analysed from the viewpoint of identifying the most promising configura ...

2024

Ultrabroadband sound control with deep-subwavelength plasmacoustic metalayers

Romain Christophe Rémy Fleury, Hervé Lissek, Stanislav Sergeev

Controlling audible sound requires inherently broadband and subwavelength acoustic solutions, which are to date, crucially missing. This includes current noise absorption methods, such as porous materials or acoustic resonators, which are typically ineffic ...

Nature Research2023

Nonlocally-resonant metamaterials

Aleksi Antoine Bossart

In this thesis, we unveil a third design path to manipulate elastic waves within architected media, distinct from the traditional phononic crystal and locally-resonant metamaterial concepts. The core innovation lies in the concept of nonlocal resonances, d ...

EPFL2023

Spectral analysis for transmission eigenvalue problems with and without the complementing conditions

Jean Louis-Alexandre Fornerod

The interior transmission eigenvalue problem is a system of partial differential equations equipped with Cauchy data on the boundary: the transmission conditions. This problem appears in the inverse scattering theory for inhomogeneous media when, for some ...

EPFL2022

Plasma-based Electroacoustic Actuator for Broadband Sound Absorption

Stanislav Sergeev

Environmental noise, mostly related to human activities, has an immense impact on public health. The development of noise reduction technologies is paramount in addressing this problem. Because of practical and economic reasons, a compact, broadband, light ...

EPFL2022

Controlled filamentation instability as a scalable fabrication approach to flexible metamaterials

Fabien Sorin, Louis Marie Philippe Martin-Monier, Pierre-Luc Eloi Piveteau, William Nicolas Duncan Esposito

Long and flexible arrays of nanowires find impactful applications in sensing, photonics, and energy harvesting. Conventional manufacturing relies largely on lithographic methods limited in wafer size, rigidity, and machine write time. Here, we report a sca ...

Nature Portfolio2022

Non-local oddities

Romain Christophe Rémy Fleury

Introducing non-local effects to metamaterials increases the complexity of their dispersion relation, which allows carefully designed elastic structures to mimic the peculiar roton behaviour of correlated quantum superfluids. ...

2021

Electromagnetic waves under nonstationary conditions, the connection with parity-time symmetry and studies on resonant systems

Theodoros Koutserimpas

In this thesis, the electromagnetic wave propagation is studied in nonstationary-medium scenarios. The electromagnetic fields under material time-modulation are shown to conserve their momentum but not their energy. The mathematical foundations and analysi ...

EPFL2021

Far field superlensing inside biological media through a nanorod lens using spatiotemporal information

Anja Skrivervik

Far field superlensing of light has generated great attention in optical focusing and imaging applications. The capability of metamaterials to convert evanescent waves to propagative waves has led to numerous proposals in this regard. The common drawback o ...

Nature Research2021

Microwave or millimeter wave passive components or devices

Romain Christophe Rémy Fleury, Maliheh Khatibi Moghaddam

A passive device comprising a hollow waveguide including first and second wall structures extending in a guiding direction, an interconnecting base extending between the wall structures and an enclosure extending between the wall structures, the enclosure ...

2021

Metasurfaces for label-free biosensing mid-infrared optics and active photonic devices

Aleksandrs Leitis

Novel two-dimensional metamaterials, known as metasurfaces, have emerged as a breakthrough platform for controlling electromagnetic wave properties at the nanoscale. These metasurfaces consist of subwavelength nanoantennas or so-called meta-atoms, which ca ...

EPFL2021

Emergent order in hydrodynamic spin lattices

Alexis Marie Frederic Goujon

Macroscale analogues(1-3) of microscopic spin systems offer direct insights into fundamental physical principles, thereby advancing our understanding of synchronization phenomena(4) and informing the design of novel classes of chiral metamaterials(5-7). He ...

NATURE PORTFOLIO2021

Subwavelength Metawaveguide Filters and Metaports

Romain Christophe Rémy Fleury, Maliheh Khatibi Moghaddam

This paper proposes an alternative technique for the design of miniaturized waveguide filters based on locally resonant metamaterials (LRMs). We implement ultrasmall metamaterial filters (metafilters) by exploiting a subwavelength (sub-λ) guiding mechanism ...

American Physical Society (APS)2021

A Subwavelength Microwave Bandpass Filter Based on a Chiral Waveguide

Romain Christophe Rémy Fleury, Maliheh Khatibi Moghaddam

Wave manipulation at a subwavelength scale has recently attracted significant interest, especially for low-frequency wave propagation, from acoustic to microwave devices. Recently, a few methods achieving subwavelength routing using locally resonant metama ...

IEEE Xplore2020

Broadband quasi-phase-matching in dispersion-engineered all-optically poled silicon nitride waveguides

Tobias Kippenberg, Camille Sophie Brès, Junqiu Liu, Rui Ning Wang, Edgars Nitiss, Ozan Yakar, Boris Zabelich

Quasi-phase-matching (QPM) has become one of the most common approaches for increasing the efficiency of nonlinear three-wave mixing processes in integrated photonic circuits. Here, we provide a study of dispersion engineering of QPM second-harmonic (SH) g ...

2020

Good Vibrations and Unknown Excitations

Dalia Salem Hassan Fahmy El Badawy

Inspired by the human ability to localize sounds, even with only one ear, as well as to recognize objects using active echolocation, we investigate the role of sound scattering and prior knowledge in regularizing ill-posed inverse problems in acoustics. In ...

EPFL2020

Robust wave transport at subwavelength scale with chiral metamaterials

Romain Christophe Rémy Fleury, Bakhtiyar Orazbayev, Nadège Sihame Kaïna

Rapid progress in all types of communication systems imposes each time more strict requirements on the communication devices, requiring having the overall device's size as small as possible, but also increasing the demands on the robustness of the transmis ...

IEEE2019

Gain enhancement of circular waveguide antennas using near-zero index metamaterials

Kosmas Tsakmakidis, Ershad Mohammadi, Foziyeh Sohrabi

In this article, a rigorous analytical methodology is introduced for designing near-zero refractive index metamaterials (NZIMs). Our proposed NZIM media is realized by three stacked layers of perforated metallic surfaces, each layer composed of a fishnet-l ...

WILEY2019

Active Times for Acoustic Metamaterials

Romain Christophe Rémy Fleury, Farzad Zangeneh Nejad

Initially proposed to achieve strong noise isolation levels beyond the mass-density law, acoustic metamaterials (AMMs) have now overturned the conventional views in all aspects of sound propagation and manipulation. In fact, within the last two decades, th ...

2019

Active acoustic resonators with reconfigurable resonance frequency, absorption, and bandwidth

Romain Christophe Rémy Fleury, Hervé Lissek, Etienne Thierry Jean-Luc Rivet, Theodoros Koutserimpas

Acoustic resonators play a key role in the development of subwavelength-sized technologies capable of interacting with airborne audible sound, from its emission and absorption to its manipulation and processing. Specifically, artificial acoustic media made ...

American Physical Society (APS)2019