arXiv subjects

V. V. Prosentsov

Publications and source records attributed to V. V. Prosentsov.

8 recordsLinked to original sources

arXiv2023

Wave scattering by objects made of small particles with pulsating permittivity

In this work we study the wave scattering by small dispersionless particles with pulsating refractive index. The scattered fields and their resonance frequencies are calculated by using scalar approximation and exponentially time-dependent permittivity. In addition, the scattering by single sphere with the pulsating permittivity is calculated numerically for different regimes of the pulsations. Our results suggest that the pulsations of the refractive index of the scatterer significantly affect the scattered field: existing resonances shift, additional resonances emerge, and deeps in the light scattering spectrum appear.

physics.optics↗

arXiv2022

Wave scattering by objects made of small particles with oscillating permittivity

Rapid advancements in the micro and nano-technology create unlimited opportunities for design of novel optical materials and their applications. Recently, the possibility of the fast refractive index modulation was demonstrated in semiconductors. In this paper we study the wave scattering by small dispersionless particles with periodically varying refractive index in scalar case by using the local perturbation method. The used formalism allows us to study theoretically and numerically the scattering by objects made of small particles of arbitrary shape and with oscillating refractive index. In this work, the field scattered by the cluster of the particles and its resonance frequencies are calculated theoretically. In addition, the results of the numerical modeling of the scattering by single cube and by cluster of cubes with oscillating permittivity are presented. It was shown that the scattered fields and their resonance frequencies are significantly affected by the oscillating permittivity: existing resonances are shifting, new scattering resonances are emerging, and deeps in the scattering spectrum are appearing.

physics.optics↗

arXiv2014

Light amplification and scattering by clusters made of small active particles: the local perturbation approach

The light amplification by finite active media is used extensively in modern optics applications. In this paper the light amplification and scattering by cluster of small particles is studied analytically and numerically with the help of the local perturbation method and phenomenological laser theory. It is shown that light amplification is possible even for one small particle, and that the amplification is more profound when the light frequency nears the frequency of the cluster's morphological resonance. Theoretical discussions are supplemented by numerical results for scattering by clusters which particles positioned at ordered and at slightly disordered positions.

physics.optics↗

arXiv2014

Dynamic scattering by cluster of small particles: local perturbation approach

The wave scattering by moving particles (dynamic scattering) is a well known physical problem routinely occurring in practice. For the particles which are much smaller than the incident wavelength, the static scattering problem can be solved by using the local perturbation method. In this paper we apply the local perturbation approach to the problem of the dynamic scattering by the cluster of small particles. We calculate the fields scattered by the cluster of moving particles. As an example, the scattered field is calculated for moving sphere in scalar approximation and in vector case.

physics.optics↗

arXiv2011

Super reflector and invisible object: analytical investigation of photonic cluster reflectivity

The reflectivity of photonic cluster is important property for nanophotonic applications especially when one needs to hide the cluster or to make it extremely visible. Currently, where are no methods clearly describing how to create the photonic cluster with the predefined reflectivity. In this paper several analytical methods are proposed to create the photonic cluster with minimal or maximal reflectivity. The proposed methods are applicable for the clusters made of small particles.

physics.optics↗

arXiv2010

Scattering optimization of photonic cluster: from minimal to maximal reflectivity

The optimization of the light scattered by photonic cluster made of small particles is studied with the help of the local perturbation method and special optimization algorithm. It was shown that photonic cluster can be optimized in a such a way that its reflectivity will be increased or decreased by several orders of magnitude for selected wavelength and direction.

physics.optics↗

arXiv2010

Resonance scattering of light by spherical photonic clusters: analytical approach

Scattering of light by the photonic clusters made of small particles is studied with the help of the quasiperiodicity condition and the local perturbation method. The analytical expression for the field scattered by the cluster is presented and the conditions of resonance scattering are found. The conditions of the zero scattering by the cluster are also found.

physics.optics↗

arXiv1996

New Mechanism of Magnetoresistance in Bulk Semiconductors: Boundary Condition Effects

We consider the electronic transport in bounded semiconductors in the presence of an external magnetic field. Taking into account appropriate boundary conditions for the current density at the contacts, a change in the magnetoresistance of bulk semiconductors is found as compared with the usual theory of galvanomagnetic effects in boundless media. New mechanism in magnetoresistance connected with the boundary conditions arises. In particular, even when the relaxation time is independent of the electron energy, magnetoresistance is not vanish.

cond-mat↗