Electrical Conductivity in Graphite Foils Produced by Rolling and Pressing.

In this research paper, the factors impacting electrical conductivity of the flexible graphite foils (GFs) produced by different forming processes, namely, either by rolling or pressing, were studied. The relationship between electrical conductivity and texture and structure that formed when producing the material was examined. Correlation was determined between the texture sharpness and anisotropy of electrical conductivity, as well as the extent of impact from the substructural characteristics on the properties' values.

Trapped mode control in metasurfaces composed of particles with the form birefringence property.

Progress in developing advanced photonic devices relies on introducing new materials, discovered physical principles, and optimal designs when constructing their components. Optical systems operating on the principles of excitation of extremely high-quality factor trapped modes (also known as the bound states in the continuum, BICs) are of great interest since they allow the implementation of laser and sensor devices with outstanding characteristics. In this paper, we discuss how one can utilize the anisotropic properties of novel materials (transition metal dichalcogenides, TMDs), particularly, the bulk molybdenum disulfide (MoS), to realize the excitation of trapped modes in dielectric metasurfaces.

Multi-band orbital angular momentum mode-division multiplexing by a compact set of microstrip ring-shaped resonator antenna.

Optical beams carrying orbital angular momentum (OAM) have received much attention due to the prospects of their use in terahertz communications, biomedical engineering, and imaging. Here we propose an antenna design for the generation of multiple beams carrying OAM with different topological states at the same frequency. The proposed OAM generator is based on a compact set of microstrip ring-shaped resonators.

Coupling coefficients for dielectric cuboids located in free space.

Practical formulas are derived for calculating the far-field radiation pattern and coupling coefficient of a rectangular dielectric resonator (cuboid) with free space as well as mutual coupling coefficients between two cuboids for their different orientations relative to each other. An approach is developed using the coupled mode theory and the perturbation theory for the Maxwell equations. The correctness of obtained formulas is checked against the full-wave numerical simulations performed by the COMSOL Multiphysics electromagnetic solver.

Approach to analysis of all-dielectric free-form antenna systems.

The analytical model is proposed for simulation of the near-field and far-field characteristics of an all-dielectric free-form antenna system. The antenna system is constructed of an array of high-refractive-index dielectric resonators. The model relies on the coupled mode theory and the perturbation theory for the Maxwell's equations.