Henrik Parsamyan

Yerevan State University | YSU

The absorption efficiency of a subwavelength conductive wire can be essentially increased in the broad microwave spectrum from 4 to \(12\,\textrm{GHz}\) by the appropriate choice of the radius and height of a wire. Such functional dependence ensures matching between the configuration and the incident field oriented by the wire axis. Theoretical res...

The absorption properties of a metamaterial absorber based on the chromium rectangular strips is studied in the long-wavelength infrared spectrum. Theoretical analysis in the framework of electrostatic approximation is performed for an individual elongated oblate ellipsoid, and the resonant condition ensuring strong absorption and negligible scatte...

The resonant response of a thin conducting rod with a finite length irradiated by microwaves polarized along its axis is observed. By using a thermoelastic optical indicator microscope it is shown that rod with a length of several half-wavelengths can serve as a resonator for axial surface waves. It is facilitated by noticeable reflections (approxi...

A metamaterial composed of thin metallic strips as an efficient broadband absorber in the mid- infrared spectrum is investigated. Here the matching between dielectric and geometrical properties of the individual elements is critical to ensure high absorption. Detailed theoretical analysis based on the electric dipole approximation is performed to c...

A metamaterial composed of thin metallic strips as an efficient broadband absorber in the mid-infrared spectrum is investigated. Here the matching between dielectric and geometrical properties of the individual elements is critical to ensure high absorption. Detailed theoretical analysis based on the electric dipole approximation is performed to ch...

Visualizations of the microwave electric and magnetic near-field distributions of radio-frequency (RF) filters were performed using the technique of thermoelastic optical indicator microscopy (TEOIM). New optical indicators based on periodic dielectric-metal structures were designed for electric field visualization. Depending on the structure orien...

The optical bistability caused by the coupling between modes of the parallel-plate waveguide and a nonlinear hemicylindrical crystal is studied using theoretical and numerical analysis. In such a system a waveguide channel is parallelly coupled to whispering gallery modes of a hemicylindrical microresonator ensuring bistable behaviour at input inte...

The optical bistability caused by the coupling between modes of the parallel-plate waveguide and a nonlinear hemicylindrical crystal is studied using theoretical and numerical analysis. In such a system a waveguide channel is parallelly coupled to whispering gallery modes of a hemicylindrical microresonator ensuring bistable behaviour at input inte...

High-resolution imaging techniques of microwave E-field and H-field can be powerful tools for visualization of the electromagnetic (EM) field distributions of materials and devices. Using the suggested method based on the optical microscopy one can visualize the E-field or H-field and temperature distributions through the thermo-elastic effect util...

The absorption efficiency of a conductive wire can be essentially increased in the broad microwave spectrum from 4 to 12 GHz by the appropriate choice of the radius and height of a wire. Such functional dependence ensures matching between the configuration and the incident field oriented by the wire axis even for relatively large values of the imag...

We propose a thin, compact, broadband, polarization and angle insensitive metamaterial absorber based on a tungsten reflector, silicon spacer and a top pattern composed of a double square-like ring resonator utilizing nickel(Ni). In such a structure, a high absorption (above 80 %) bandwidth ~ 4.8 μm from 3.52 up to 8.32 μm corresponding to the rela...

We propose a thin, compact, broadband, polarization and angle insensitive metamaterial absorber based on a tungsten reflector, silicon spacer and a top pattern composed of a double square-like ring resonator utilizing nickel(Ni). In such a structure, a high absorption (above 80 %) bandwidth ~ 4.8 μm from 3.52 up to 8.32 μm corresponding to the rela...

We have shown that a structure composed of a semiconductor hemicylinder and a dielectric waveguide separated by a thin metal layer permits efficient and easy light control. In such a system, it is possible to ensure matching between TE and TM modes of a low refractive index waveguide with the corresponding whispering gallery modes of the hemicylind...

The semicylindrical microresonator with relatively simple excitation with a plane wave is studied. The resonator is formed on the base of the dielectric/metal/dielectric structure, where the wave energy penetrates into resonator through a thin metal layer and stored in a semicylindrical dielectric with high permittivity. The proposed microresonator...

We suggest to exploit dielectric-metal core-shell nanostructures for efficient resonant and yet broadband absorption of infrared radiation with deeply subwavelength configurations. Realizing that nanostructures would efficiently absorb radiation only when their dielectric properties match those of the environment and making use of the effective med...

We suggest to exploit dielectric-metal core-shell nanostructures for efficient resonant and yet broadband absorption of infrared radiation with deeply subwavelength configurations. Realizing that nanostructures would efficiently absorb radiation only when their dielectric properties match those of the environment and making use of the effective med...

Glucose concentration in the aqueous solution was measured using a microwave metamaterial sensor based on the modified Hilbert curve of the first fractal order. In order to increase the system sensitivity at fixed meta-element sizes, the design of the sensor was optimized by using finite element method. It was observed that $ S $ parameters of the...

A semicylindrical microresonator with relatively simple excitation by a plane wave is studied. The resonator is formed on the base of a dielectric/metal/dielectric structure, where the wave energy penetrates into the resonator through a thin metal layer and is stored in a semicylindrical dielectric with high permittivity. The proposed microresonato...

The microwave fractal bandpass filters based on modified Hilbert shaped curves of the first and second fractal orders are experimentally and numerically analyzed. As a substrate Al2O3 ceramic covered by the thin silver layer with thickness of 50 μm was used. The laser patterning technique was used to design the structures of filters. The filter bas...

The localized surface plasmon resonance (LSPR) of gold and silver spherical and cubic nanoparticles (NP), as well as NP dimers is studied. We use numerical simulations based on finite element method to derive extinction cross-sections (ECS) and LSPR wavelengths of the investigated structures. Study of the dependence of the LSPR of the cubic NPs on...

Экспериментально и численно проанализированы микроволновые фрак- тальные полосовые фильтры, основанные на модифицированных кривых Гиль- берта первого и второго фрактальных порядков. В качестве подложки была использована керамика Al2O3, поверхность которой покрыта слоем серебра тол- щиной 50 мкм. При создании структур фильтров использовалась техника...

A system of two, coupled semicylindrical microresonator with relatively simple excitation by a plane wave is studied and Fano resonance was obtained there. The resonator is formed on the base of a dielectric/metal/dielectric structure, where the wave energy penetrates into the resonator through a thin metal layer and is stored in a semicylindrical...