Nanolens based on metallic nanorod has been considered as a prospective candidate for transportin... more Nanolens based on metallic nanorod has been considered as a prospective candidate for transporting subwavelength information. Such a lens is tuned to a particular frequency by tailoring the length of the nanorod. In this paper, we have investigated the impact of filling ratio on the subwavelength imaging capabilities of such a lens. Through full-wave electromagnetic simulation, we have demonstrated that the imaging performance of silver (Ag) nanorod array does not only depend on the length and periodicity but also on the filling ratio or the radius of the nanorod. We have studied this impact for nanorod having different cross-sectional shapes such as cylindrical and triangular and examined their performances for various filling ratios.
2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, 2013
ABSTRACT We report our recent achievements in tuning metamaterials with light. We introduce a nov... more ABSTRACT We report our recent achievements in tuning metamaterials with light. We introduce a novel approach to design metamaterials with sign-varying nonlinear response. For this purpose, we use split-ring resonators loaded by photodiodes and varactor diodes. A non-monotonic frequency shift of the resonance frequency depending on incident microwave power is demonstrated. Finally, we show how the nonlinear response of photosensitive metamaterials can be directly controlled by light coupling.
We suggest a novel type of photonic topological edge states in zigzag arrays of dielectric nanopa... more We suggest a novel type of photonic topological edge states in zigzag arrays of dielectric nanoparticles based on optically induced magnetic Mie resonances. We verify our general concept by the proof-of-principle microwave experiments with dielectric spherical particles, and demonstrate, experimentally, the ability to control the subwavelength topologically protected electromagnetic edge modes by changing the polarization of the incident wave.
We study the scattering of polaritons by free electrons in hyperbolic photonic media and demonstr... more We study the scattering of polaritons by free electrons in hyperbolic photonic media and demonstrate that the unconventional dispersion and high local density of states of electromagnetic modes in composite media with hyperbolic dispersion can lead to a giant Compton-like shift and dramatic enhancement of the scattering cross section. We develop a universal approach to study multiphoton processes in nanostructured media and derive the intensity spectrum of the scattered radiation for realistic metamaterial structures.
2013 SBMO/IEEE MTT-S International Microwave & Optoelectronics Conference (IMOC), 2013
ABSTRACT We introduce a novel concept of superdirective nanoantennas based on the generation of h... more ABSTRACT We introduce a novel concept of superdirective nanoantennas based on the generation of higher-order optically-induced magnetic multipoles. Such an all-dielectric nanoantenna can be realized as an optically small spherical dielectric nanoparticle with a notch excited by a point source located in the notch. Proposed superdirectivity effect is not associated with high dissipative losses, because of the magnetic nature of the nanoantenna operation. For these dielectric nanoantennas we predict the effect of the beam steering at the nanoscale characterized by a subwavelength sensitivity of the beam radiation direction to the source position. We confirm the predicted effects experimentally through scaling to the microwave frequency range.
2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, 2013
ABSTRACT We develop a method for fabricating hyperbolic metamaterials for terahertz (THz) applica... more ABSTRACT We develop a method for fabricating hyperbolic metamaterials for terahertz (THz) applications. We prepare a porous silicon matrix with a triangular lattice of holes, which we fill with copper by means of electrochemical deposition. We study transmission properties of this wire medium using THz time-domain spectroscopy, and demonstrate hyperbolic media properties.
2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, 2013
ABSTRACT In this paper, we report about the first experimental verification of evanescent waves e... more ABSTRACT In this paper, we report about the first experimental verification of evanescent waves enhancement inside wire metamaterial. The enhancement is originated by resonant pumping of standing waves inside the wire metamaterial. An excellent agreement between the experimental data and numerical results is found. Furthermore the applicability of this concept for improvement of magnetic resonance imaging is demonstrated.
Journal of Communications Technology and Electronics, 2014
ABSTRACT The possibility of transfer of the spatial distribution of the near-zone RF magnetic fie... more ABSTRACT The possibility of transfer of the spatial distribution of the near-zone RF magnetic field recorded by receiving coils during magnetic resonance imaging with the use of an endoscope designed from an extremely anisotropic metamaterial is considered. Application of such a material can lead to an increase in the image resolution and/or reduction of the object scanning time in the tomograph. Possibilities of the endoscope for the undistorting transfer of the spatial distribution of the alternating magnetic field through significant distances are theoretically studied and transfer of different spatial field distributions from the isocenter of the tomograph to the region of weak static magnetic field is experimentally demonstrated. The dependence of the quality of obtained images on positions receiving coils in the endoscope is studied. It is found that, in addition to the image transfer with a small distortion, it is possible to significantly increase the signal-to-noise ratio by pumping standing waves in a medium consisting of parallel wires.
Subwavelength structures demonstrate many unusual optical properties which can be employed for en... more Subwavelength structures demonstrate many unusual optical properties which can be employed for engineering of a new generation of functional metadevices, as well as controlled scattering of light and invisibility cloaking. Here we demonstrate that the suppression of light scattering for any direction of observation can be achieved for a uniform dielectric object with high refractive index, in a sharp contrast to the cloaking with multilayered plasmonic structures suggested previously. Our finding is based on the novel physics of cascades of Fano resonances observed in the Mie scattering from a homogeneous dielectric rod. We observe this effect experimentally at microwaves by employing high temperature-dependent dielectric permittivity of a glass cylinder with heated water. Our results open a new avenue in analyzing the optical response of high-index dielectric nanoparticles and the physics of cloaking.
We perform complex investigation of the distribution of electromagnetic fields in the vicinity of... more We perform complex investigation of the distribution of electromagnetic fields in the vicinity of an array of silver nanoantennas, which can operate as an efficient light trapping structure in the visible spectral range. In theory, this array should support unusual collective modes that possess an advantageous distribution of local electric fields, ensuring both strong field localization beneath nanoantennas and a low level of optical losses inside the metal. Using an aperture-type near-field scanning optical microscope (NSOM), we obtain near-field patterns that show excellent agreement with the NSOM signal, directly reconstructed from rigorous numerical simulations using an approach based on the electromagnetic reciprocity theorem. The agreement between theory and experiment allows us to claim the first-time experimental verification of the existence of collective modes with such properties in an array of silver nanoantennas. The confirmation of this physical phenomenon opens the d...
Nanolens based on metallic nanorod has been considered as a prospective candidate for transportin... more Nanolens based on metallic nanorod has been considered as a prospective candidate for transporting subwavelength information. Such a lens is tuned to a particular frequency by tailoring the length of the nanorod. In this paper, we have investigated the impact of filling ratio on the subwavelength imaging capabilities of such a lens. Through full-wave electromagnetic simulation, we have demonstrated that the imaging performance of silver (Ag) nanorod array does not only depend on the length and periodicity but also on the filling ratio or the radius of the nanorod. We have studied this impact for nanorod having different cross-sectional shapes such as cylindrical and triangular and examined their performances for various filling ratios.
2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, 2013
ABSTRACT We report our recent achievements in tuning metamaterials with light. We introduce a nov... more ABSTRACT We report our recent achievements in tuning metamaterials with light. We introduce a novel approach to design metamaterials with sign-varying nonlinear response. For this purpose, we use split-ring resonators loaded by photodiodes and varactor diodes. A non-monotonic frequency shift of the resonance frequency depending on incident microwave power is demonstrated. Finally, we show how the nonlinear response of photosensitive metamaterials can be directly controlled by light coupling.
We suggest a novel type of photonic topological edge states in zigzag arrays of dielectric nanopa... more We suggest a novel type of photonic topological edge states in zigzag arrays of dielectric nanoparticles based on optically induced magnetic Mie resonances. We verify our general concept by the proof-of-principle microwave experiments with dielectric spherical particles, and demonstrate, experimentally, the ability to control the subwavelength topologically protected electromagnetic edge modes by changing the polarization of the incident wave.
We study the scattering of polaritons by free electrons in hyperbolic photonic media and demonstr... more We study the scattering of polaritons by free electrons in hyperbolic photonic media and demonstrate that the unconventional dispersion and high local density of states of electromagnetic modes in composite media with hyperbolic dispersion can lead to a giant Compton-like shift and dramatic enhancement of the scattering cross section. We develop a universal approach to study multiphoton processes in nanostructured media and derive the intensity spectrum of the scattered radiation for realistic metamaterial structures.
2013 SBMO/IEEE MTT-S International Microwave & Optoelectronics Conference (IMOC), 2013
ABSTRACT We introduce a novel concept of superdirective nanoantennas based on the generation of h... more ABSTRACT We introduce a novel concept of superdirective nanoantennas based on the generation of higher-order optically-induced magnetic multipoles. Such an all-dielectric nanoantenna can be realized as an optically small spherical dielectric nanoparticle with a notch excited by a point source located in the notch. Proposed superdirectivity effect is not associated with high dissipative losses, because of the magnetic nature of the nanoantenna operation. For these dielectric nanoantennas we predict the effect of the beam steering at the nanoscale characterized by a subwavelength sensitivity of the beam radiation direction to the source position. We confirm the predicted effects experimentally through scaling to the microwave frequency range.
2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, 2013
ABSTRACT We develop a method for fabricating hyperbolic metamaterials for terahertz (THz) applica... more ABSTRACT We develop a method for fabricating hyperbolic metamaterials for terahertz (THz) applications. We prepare a porous silicon matrix with a triangular lattice of holes, which we fill with copper by means of electrochemical deposition. We study transmission properties of this wire medium using THz time-domain spectroscopy, and demonstrate hyperbolic media properties.
2013 7th International Congress on Advanced Electromagnetic Materials in Microwaves and Optics, 2013
ABSTRACT In this paper, we report about the first experimental verification of evanescent waves e... more ABSTRACT In this paper, we report about the first experimental verification of evanescent waves enhancement inside wire metamaterial. The enhancement is originated by resonant pumping of standing waves inside the wire metamaterial. An excellent agreement between the experimental data and numerical results is found. Furthermore the applicability of this concept for improvement of magnetic resonance imaging is demonstrated.
Journal of Communications Technology and Electronics, 2014
ABSTRACT The possibility of transfer of the spatial distribution of the near-zone RF magnetic fie... more ABSTRACT The possibility of transfer of the spatial distribution of the near-zone RF magnetic field recorded by receiving coils during magnetic resonance imaging with the use of an endoscope designed from an extremely anisotropic metamaterial is considered. Application of such a material can lead to an increase in the image resolution and/or reduction of the object scanning time in the tomograph. Possibilities of the endoscope for the undistorting transfer of the spatial distribution of the alternating magnetic field through significant distances are theoretically studied and transfer of different spatial field distributions from the isocenter of the tomograph to the region of weak static magnetic field is experimentally demonstrated. The dependence of the quality of obtained images on positions receiving coils in the endoscope is studied. It is found that, in addition to the image transfer with a small distortion, it is possible to significantly increase the signal-to-noise ratio by pumping standing waves in a medium consisting of parallel wires.
Subwavelength structures demonstrate many unusual optical properties which can be employed for en... more Subwavelength structures demonstrate many unusual optical properties which can be employed for engineering of a new generation of functional metadevices, as well as controlled scattering of light and invisibility cloaking. Here we demonstrate that the suppression of light scattering for any direction of observation can be achieved for a uniform dielectric object with high refractive index, in a sharp contrast to the cloaking with multilayered plasmonic structures suggested previously. Our finding is based on the novel physics of cascades of Fano resonances observed in the Mie scattering from a homogeneous dielectric rod. We observe this effect experimentally at microwaves by employing high temperature-dependent dielectric permittivity of a glass cylinder with heated water. Our results open a new avenue in analyzing the optical response of high-index dielectric nanoparticles and the physics of cloaking.
We perform complex investigation of the distribution of electromagnetic fields in the vicinity of... more We perform complex investigation of the distribution of electromagnetic fields in the vicinity of an array of silver nanoantennas, which can operate as an efficient light trapping structure in the visible spectral range. In theory, this array should support unusual collective modes that possess an advantageous distribution of local electric fields, ensuring both strong field localization beneath nanoantennas and a low level of optical losses inside the metal. Using an aperture-type near-field scanning optical microscope (NSOM), we obtain near-field patterns that show excellent agreement with the NSOM signal, directly reconstructed from rigorous numerical simulations using an approach based on the electromagnetic reciprocity theorem. The agreement between theory and experiment allows us to claim the first-time experimental verification of the existence of collective modes with such properties in an array of silver nanoantennas. The confirmation of this physical phenomenon opens the d...
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Papers by Pavel Belov