Related papers: Tunable Asymmetric Acoustic Absorption in Ventilat…
Audio-visual speech recognition (AVSR) combines audio-visual modalities to improve speech recognition, especially in noisy environments. However, most existing methods deploy the unidirectional enhancement or symmetric fusion manner, which…
Sound absorption at low frequencies still remains a challenge in both scientific research and engineering practice. Natural porous materials are ineffective in this frequency range, as well as acoustic resonators which present too narrow…
We present experimental demonstration of electronically tunable metamaterial perfect absorbers in the terahertz regime. By incorporation of active liquid crystal into strategic locations within the metamaterial unit cell we are able to…
We present the practicality of structuring ceramic tiles for enhancing sound absorption on rigid walls. The cornerstone of our methodology is to structure walls with cavities so that walls effectively behave as heterogeneous absorbing…
The investigation of metasurface, which is of great current interest, has opened up new degrees of freedom to research metamaterials. In this paper, we propose an ultrathin acoustic metasurface consisting of a series of structurally simple…
We theoretically and experimentally report sub-wavelength resonant panels for low-frequency quasi-perfect sound absorption including transmission by using the accumulation of cavity resonances due to the slow sound phenomenon. The…
Two-dimensional, resonant scanners have been utilized in a large variety of imaging modules due to their compact form, low power consumption, large angular range, and high speed. However, resonant scanners have problems with non-optimal and…
On the quest towards full control over wave propagation, the development of compact devices that allow asymmetric response is a challenge. In this Letter, we introduce a new paradigm for the engineering of asymmetry in planar structures,…
Resonant absorption and mode conversion are both extensively studied mechanisms for wave "absorption" in solar magnetohydrodynamics (MHD). But are they really distinct? We re-examine a well-known simple resonant absorption model in a cold…
We propose to use logarithmic spiral resonators for efficient absorption of microwaves. By combining their scale invariant geometries and Fabry-Perot-type resonances stemming from the fundamental TM mode, we realize a microwave metasurface…
Mode conversion and resonant absorption are crucial mechanisms for wave transport and absorption. Scaling behavior of mode conversion or resonant absorption is well-known for electromagnetic and MHD waves in planar geometry. Our recent…
This paper describes a new kind of acoustic metasurface with multiply resonant units, which have previously been used to induce multiple resonances and effectively produce negative mass density and bulk/shear moduli. The proposed acoustic…
Surface acoustic wave (SAW) devices are widely used in sensing and biosensing but generally suffer from strong attenuation in liquid environments. Conventional approaches rely on reflectors to reduce these losses, yet these components…
We describe here a class of acoustic metamaterials with fractal Hilbert space-filling and coiled geometry with equal tortuosity for noise mitigation. Experiments are performed using a four-microphone impedance tube and benchmarked against…
Optical geometric-phase metasurface provides a robust and efficient means for light control by simply manipulating the spatial orientations of the in-plane anisotropic meta-atoms, where polarization conversion plays a vital role. However,…
We report on experiments of perfect absorption for surface gravity waves impinging a wall structured by a subwavelength resonator. By tuning the geometry of the resonator, a balance is achieved between the radiation damping and the…
In this paper, we study the behaviour of the coupled subwavelength resonant modes when two high-contrast acoustic resonators are brought close together. We consider the case of spherical resonators and use bispherical coordinates to derive…
Wave absorption metamaterials have been an enduring topic over the past two decades, propelled not only by novel scientific advances, but also by their extensive application potential. In this review, we aim to provide some general insights…
A thin metamaterial slab comprising a dielectric spacer sandwiched between a metallic grating and a ground plane is shown to possess spatially coherent surface resonance states that span a large frequency range and can be tuned by…
In this paper, we report on the design, fabrication, and experimental characterization of a 3D single-port labyrinthine acoustic metamaterial. By using curled perforations with one end closed and with appropriate loss inside, the proposed…