arXiv subjects

M. I. Tribelsky

Publications and source records attributed to M. I. Tribelsky.

3 recordsLinked to original sources

arXiv2026

High-Accuracy Semi-Analytical Method for Solving the Problem of Electromagnetic Wave Scattering by Arbitrary Ensembles of Parallel Circular Cylinders

A method is proposed for solving the two-dimensional problem of electromagnetic wave scattering by a cluster of an arbitrary number of parallel, infinitely long, homogeneous, non-overlapping right circular cylinders. The cylinders may have arbitrary radii and complex permittivities, and their axes, while remaining parallel, may occupy arbitrary positions in the transverse plane. The solution is constructed using an analytical expansion of the electromagnetic field in cylindrical harmonics. Multiple scattering is taken into account by Graf's addition theorem, which leads to a system of linear equations for the expansion coefficients. This system is solved numerically with condition number monitoring and, when necessary, extended-precision arithmetic, followed by a multistage verification of convergence. The method provides numerically verified solutions with controlled accuracy over a wide range of parameters, including densely packed subwavelength configurations. As an example, scattering of a normally incident, linearly polarized monochromatic plane wave by a subwavelength cluster of three identical aluminum nanocylinders (nanowires) is studied. The scattering, absorption, and extinction cross sections, as well as the scattering indicatrix, are computed and analyzed. Streamlines of the Poynting vector field are constructed, demonstrating redistribution of the energy flux between the cylinders of the cluster and the formation of localized regions of field enhancement near their surfaces.

physics.optics↗

arXiv2024

Field structures and singularities in subwavelength optics

A brief overview of the current state of the problem of electromagnetic field singularities arising from the refraction and scattering of light by material objects is given. The discussion begins with caustics arising from ray tracing in geometric optics and consistently moves toward increasing the accuracy of consideration and decreasing the scale, ending with a description of singularities in light scattering by subwavelength particles. Common and distinctive features of various types of singularities, the role of the symmetry of the problem and the law of conservation of energy are revealed. Physical foundations and methods for overcoming the diffraction limit are discussed. The theoretical description is illustrated by experimental examples. Various practical applications of the effects under consideration are indicated.

physics.optics↗

arXiv2015

Giant In-Particle Field Concentration and Fano Resonances at Light Scattering by High-Refractive Index Particles

A detailed analytical inspection of light scattering by a particle with high refractive index m+iκand small dissipative constant κis presented. We have shown that there is a dramatic difference in the behavior of the electromagnetic field within the particle (inner problem) and the scattered field outside it (outer problem). With an increase in m at fix values of the other parameters, the field within the particle asymptotically converges to a periodic function of m. The electric and magnetic type Mie resonances of different orders overlap substantially. It may lead to a giant concentration of the electromagnetic energy within the particle. At the same time, we demonstrate that identical transformations of the solution for the outer problem allow to present each partial scattered wave as a sum of two partitions. One of them corresponds to the m-independent wave, scattered by a perfectly reflecting particle and plays the role of a background, while the other is associated with the excitation of a sharply-m-dependent resonant Mie mode. The interference of the partitions brings about a typical asymmetric Fano profile. The explicit expressions for the parameters of the Fano profile have been obtained "from the first principles" without any additional assumptions and/or fitting. In contrast to the inner problem, at an increase in m the resonant modes of the outer problem die out, and the scattered field converges to the universal, m-independent profile of the perfectly reflecting sphere. Numerical estimates of the discussed effects for a gallium phosphide particle are presented.

physics.optics↗