We demonstrate the near-field coupling and energy transfer between photoexcited dye molecules and guided modes in layers of strongly absorbing dielectrics. The dye molecules decay by exciting long-range guided modes (LRGMs) in a thin layer of chalcogenide glass. These modes can exist in spite of the very large absorption of the material forming the layer. The LRGMs are detected by coupling then...

Strong absorption of sound is often caused by the conversion of sound energy into heat. When this happens, it is not possible to study the interaction of sound with the absorbing material by means of reflected sound characteristics, because there is no reflected sound. Detecting for example the distance that sound travels in a strongly absorbing material, can be done by heat detection systems. ...

We review some recent results on the relations between sandpiles and a class of absorbing state phase transitions. We use the concept of fixed energy sandpiles (FES), in which external driving and dissipation are absent. FES are shown to exhibit an absorbing state transition with critical properties coinciding with those of the corresponding sandpile model. We propose a set of Langevin equation...

The car front bumper system needs to meet the requirements of both pedestrian safety and low-speed impact which are somewhat contradicting. This study aims to design a new kind of modular self-adaptive energy absorber of the front bumper system which can balance the two performances. The X-shaped energy-absorbing structure was proposed which can enhance the energy absorption capacity during imp...

The FeCo/Fe3O4 nanocomposite was synthesized using the hydrothermal approach, in which the FeCo alloy and Fe3O4 are formed by one step. The structure of the FeCo/Fe3O4 nanocomposite was characterized by means of Scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray energy-dispersive spectrometer spectroscopy (EDX). They show that the mass ratio of FeCo/Fe3O4 strongly depends on ...

We propose and theoretically investigate an efficient solar light absorber based on a multilayer structure consisting of tungsten nanoparticle layers and SiO2 layers. According to our calculation, average absorbance over 94% is achieved in the wavelength range between 400 and 2500 nm for the proposed absorber. The excellent performance of the absorber can be attributed to the localized surface ...

We study a one-dimensional fixed-energy version (that is, with no input or loss of particles) of Manna's stochastic sandpile model. The system has a continuous transition to an absorbing state at a critical value of the particle density, and exhibits the hallmarks of an absorbing-state phase transition, including finite-size scaling. Critical exponents are obtained from extensive simulations, w...

We propose to use double negative (DNG) metamaterial slabs to build effective super-absorbers and perfect nanodetectors for single divergent sources. We demonstrate by numerical simulations that an absorbing nanoparticle properly placed inside a DNG slab back-covered with a perfect electric conductor or perfect magnetic conductor mirror can absorb up to 100% radiation energy of a single dipole ...

With the aim of finding an optimal shape for a traffic noise absorber, we consider the boundary shape optimization problem of minimizing the total acoustic energy for a fixed frequency. The model is described by the boundary-value problem for the Helmholtz equation. All boundaries of the domain are supposed to be fixed except one part where the absorbing Robin boundary condition is imposed. The...

Solar energy is the most “available”, ecological and clean energy. This energy can be used in active or passive mode. The active mode implies the transformation of solar energy into a useful energy. The solar energy can be transformed into thermal energy, using solar collectors. In these collectors, the active and the most important element is the absorber, material which performs the absorptio...