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A bubble meta-screen is an exceptionally effective and low frequency resonator which can be optimized in order to exactly balance the energy provided by radiative process and lost under a viscous mechanism (critical coupling). Under this…
Hypersound Absorption of acoustic phonons having $ql>>1$ in a degenerate Carbon Nanotube (CNT) with linear energy dispersion near the Fermi level was theoretically studied. The general expression for the absorption coefficient ($\Gamma$)…
Positive buildings in energy are, nowadays, a recurrent objective of many researches in the construction and energetic efficiency domain. Furthermore, to achieve this objective, some studies about active and reactive walls have been carried…
The study of diffusion and low frequency vibrational motions of particles on metal surfaces is of paramount importance; it provides valuable information on the nature of the adsorbate-substrate and the substrate-substrate interactions. In…
A simple molecular thermodynamic approach is applied to the study of the adsorption of gases of chain molecules on solid surfaces. We use a model based on the Statistical Associating Fluid Theory for Variable Range (SAFT-VR) potentials [A.…
Supersonic pre-transitional boundary layers flowing over porous flat and concave surfaces are studied using numerical and asymptotic methods. The porous wall is composed of thin equally-spaced cylindrical microcavities. The flow is…
The ability to control and direct acoustic energy is essential for many engineering applications such as vibration and noise control, invisibility cloaking, acoustic sensing, energy harvesting, and phononic switching and rectification. The…
The continuous surge of environmental noise levels has become a vital challenge for humanity. Earlier studies have reported that prolonged exposure to loud noise may cause auditory and non-auditory disorders. Therefore, there is a growing…
Glasses are known to exhibit quantitative universalities at low temperatures, the most striking of which is the ultrasonic attenuation coefficient 1/Q. In this work we develop a theory of coupled generic blocks with a certain randomness…
The adsorption of rare gases on metal surfaces serve as the paradigm of weak adsorption where it is typically assumed that the adsorbate occupies maximally coordinated hollow sites. Density-functional theory calculations using the…
We describe a method for calculating the probability with which the wall of a plasma absorbs an electron at low energy. The method, based on an invariant embedding principle, expresses the electron absorption probability as the probability…
Nanoporous materials are a promising platform for thermoelectrics in that they offer high thermal conductivity tunability while preserving good electrical properties, a crucial requirement for high- effciency thermal energy conversion.…
High-frequency acoustic wave transducers, vibrating at gigahertz (GHz), favored for their compact size, are not only dominating the front-end of mobile handsets but are also expanding into various interdisciplinary fields, including quantum…
We study phonon-mediated adsorption and desorption of an electron at dielectric surfaces with deep polarization-induced surface potentials where multi-phonon transitions are responsible for electron energy relaxation. Focusing on…
Nanostructured semiconducting alloys obtain ultra-low thermal conductivity as a result of the scattering of phonons with a wide range of mean-free-paths (MFPs). In these materials, long-MFP phonons are scattered at the nanoscale boundaries…
Acoustic metamaterials are increasingly being considered as a viable technology for sound insulation. Fractal patterns constitute a potentially groundbreaking architecture for acoustic metamaterials. We describe in this work the behaviour…
Third sound measurements of superfluid $^4$He thin films adsorbed on 10 nm diameter multiwall carbon nanotubes are used to probe the superfluid onset temperature as a function of the film thickness, and to study the temperature dependence…
Dissipation of electromagnetic energy through absorption is a fundamental process that underpins phenomena ranging from photovoltaics to photography, analytical spectroscopy, photosynthesis, and human vision. Absorption is also a dynamic…
The coupling of atomic vibrations to electronic excitations - traditionally understood to be a source of energy loss in semiconductors - has recently been explored in photosynthetic light harvesting as a means to circumvent dissipation by…
In this paper we develop a model to describe the diffusion process in a porous medium. For the observed decrease in current yield, we propose other causes than difference in diffusivity, which we consider unaltered by the porous medium. The…