Matlabjon Sattorov - Academia.edu (original) (raw)

Papers by Matlabjon Sattorov

2019 International Vacuum Electronics Conference (IVEC)

Uniform, highly conductive, thin film field emitters are in immense need for future development o... more Uniform, highly conductive, thin film field emitters are in immense need for future development of high power compact terahertz(THz) vacuum electronic devices(VED). Reduced graphene oxide(rGO) based free standing film as high current sheet beam cathode is fabricated by hydrothermal method. This hydrothermal method facilitates highly conductive, thin, compact film. We achieved to get few micrometers to sub-micrometer thick film which is much thinner than conventional vacuum filtered film resulting in higher field enhancement factor, current density, and current. This approach can successfully establish a fabrication method for uniform, thin high current field emitter for high power THz VEDs.

2019 44th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), 2019

By manipulating Fano resonance in metallic metamaterial, trapping and releasing of electromagneti... more By manipulating Fano resonance in metallic metamaterial, trapping and releasing of electromagnetic wave can be controlled. Simply, by varying the size of structural asymmetry to the proposed metallic slit structure, Q factor of trapped mode in metallic metamaterial can be tailored. We show that optimizing the electromagnetic property of Fano metamaterial can maximizes the interaction between convection electron and trapped mode, which gives significantly high efficiency of Cerenkov radiation larger than one from the ordinary Cerenkov and Smith-Purcell effects by order of two. We also observed inversion of the spectral asymmetry and the phase shift of high-Q trapped modes in subwavelength slits by manipulating the direction of the structural asymmetry of unit cell paving the way for full control of Fano resonances This finding is thought to be useful for many other potential applications other than Cerenkov lasing such as sensing and optical switching.

Electronics, 2021

The failure threshold time of semiconductors caused by the impact of irradiated high-power electr... more The failure threshold time of semiconductors caused by the impact of irradiated high-power electromagnetic waves (HPEM) is experimentally studied. A SN7442 integrated circuit (IC) is placed in an emulator with a WR430 closed waveguide and is irradiated by HPEM generated from a magnetron oscillator. The state of the SN7442 component is observed by a light-emitting diode (LED) detector and the voltage measured in the SN7442 component. As the magnitude of the electric field in the HPEM is varied from 24 kV/m to 36 kV/m, the failure threshold time falls from 195 s to 17 s with dependence of the irradiated electric field (E) on the failure threshold time (T) from T~E−12 to a T~E−6.

IEEE Access, 2021

High-power microwave sources applied to a directed-energy weapon can lead to permanent damage by ... more High-power microwave sources applied to a directed-energy weapon can lead to permanent damage by radiating concentrated energy in a specific direction to disturb or overload electronic equipment. The effect analysis on the target, such as electronics exposed to electromagnetic pulse, should be considered as an important factor in determining the performance of high-power microwave sources and conducting experimental evaluations. In this study, a magnetically insulated transmission line oscillator, one of the representative high-power microwave sources based on vacuum electronics device, was constructed and experimental analysis with respect to electromagnetic pulse effects was performed. The specification of the magnetically insulated transmission line oscillator used in this study corresponded to 3 GW of high-power electromagnetic wave pulses operating at L-band. The power efficiency was approximately 10-15%. For effective targeting, a Vlasov antenna that converts TM 01 mode to TE 11 mode was designed and fabricated. The radiation pattern was confirmed via fluorescent lamps, and to confirm the effect of the directed-energy weapon on the target, an effect analysis was performed using a portable electronic device as a sample. Furthermore, the electric field was measured with a D-dot probe and quantified and compared. This study presents a future blueprint of the value of the directed-energy weapon by predicting the radiant output power of the weapon in the far-field region after it is mounted on a movable ground vehicle or unmanned aerial vehicle. INDEX TERMS High power microwave (HPM), directed-energy weapon (DEW), electromagnetic pulse (EMP), magnetically insulated transmission line oscillator (MILO).

Proceedings of the National Academy of Sciences, 2020

Significance Why have primates evolved epidermal ridges on the volar regions of the hands and fee... more Significance Why have primates evolved epidermal ridges on the volar regions of the hands and feet and with a much greater density of sweat glands than flat skin, which respond to anxiety rather than act as a thermoregulation mechanism? During contact with solid objects, the ridges are important for grip and precision manipulation by regulating moisture levels from either external sources or the sweat pores so that the friction is maximized and catastrophic slip is inhibited. An understanding of the underlying mechanisms involved has become particularly important with the almost ubiquitous contact of the finger pads with flat screens and recent developments in haptic feedback using ultrasonic vibrations for which the performance is critically related to the friction.

Review of Scientific Instruments, 2020

ARTICLES YOU MAY BE INTERESTED IN Variable beam entrance Faraday cup system for pulsed electron b... more ARTICLES YOU MAY BE INTERESTED IN Variable beam entrance Faraday cup system for pulsed electron beam current profile characterization Review of Scientific Instruments 91, 113303 (2020);

ChemPhysChem, 2020

We present an atomistic simulation scheme for the determination of the hydration number (h) of aq... more We present an atomistic simulation scheme for the determination of the hydration number (h) of aqueous electrolyte solutions based on the calculation of the water dipole reorientation dynamics. In this methodology, the time evolution of an aqueous electrolyte solution generated from ab initio molecular dynamics simulations is used to compute the reorientation time of different water subpopulations. The value of h is determined by considering whether the reorientation time of the water subpopulations is retarded with respect to bulk-like behavior. The application of this computational protocol to magnesium chloride (MgCl 2) solutions at different concentrations (0.6-2.8 mol kg À 1) gives h values in excellent agreement with experimental hydration numbers obtained using GHz-to-THz dielectric relaxation spectroscopy. This methodology is attractive because it is based on a well-defined criterion for the definition of hydration number and provides a link with the molecular-level processes responsible for affecting bulk solution behavior. Analysis of the ab initio molecular dynamics trajectories using radial distribution functions, hydrogen bonding statistics, vibrational density of states, water-water hydrogen bonding lifetimes, and water dipole reorientation reveals that MgCl 2 has a considerable influence on the hydrogen bond network compared with bulk water. These effects have been assigned to the specific strong Mg-water interaction rather than the Cl-water interaction.

The Journal of Korean Institute of Electromagnetic Engineering and Science, 2018

AIP Advances, 2019

Ionizing radiation in electronics from the Compton scattering of quasi-stationary particles gener... more Ionizing radiation in electronics from the Compton scattering of quasi-stationary particles generated by characteristic and Bremsstrahlung x rays AIP Advances 10, 055110 (2020);

Advanced Optical Materials, 2018

development of such CR-based applications is limited by thermal and dielectric breakdown issues. ... more development of such CR-based applications is limited by thermal and dielectric breakdown issues. [3,4] Another limitation is that, due to the velocity threshold, large facilities are required to generate highly energetic particles. These limitations restrict the upper and lower size and performance boundaries in vital applications. Nowadays, metallic metamaterial devices have been proposed, which overcome the limitations of conventional Cerenkov devices to realize reversed CR from the negative-refractive index, [5] the ultralow threshold of kinetic energy in hyperbolic metamaterials, [6] and various metallic metamaterials comprised of subwavelength slits. [7-9] However, the realization of a high quality factor (Q) is still an outstanding roadblock for practical Cerenkov devices. Previous works on Cerenkov lasing (CL) using mirrors were limited by a lower electron beam impedance due to the interaction device and the radio-frequency (RF) coupling mechanism. [4,10] Here, to achieve a high Q for highly efficient CL, we focus on maximally trapping the electromagnetic Cerenkov radiation wave to extend its interaction with the electron beam and on controlling the radiation damping, as has been described in Rayleigh scattering to maximize the efficiency of CL. In this paper, we demonstrate that the interplay between an extremely low group velocity from the infinite transverse permittivity of the anisotropic metamaterials and the subradiant A high-quality-factor (high-Q) metallic Fano metamaterial is demonstrated both experimentally and theoretically. This material is suitable for highly efficient Cerenkov lasing in which subwavelength metallic slits are arranged to form asymmetric unit cells. In contrast to conventional dielectric Cerenkov or Smith-Purcell devices, in the proposed device, convection electrons traverse the high-Q metallic metamaterial. The interplay between an extremely low group velocity from the infinite transverse permittivity of the anisotropic metamaterial and the subradiant damping from a Fano-type slit mode is shown to be responsible for the high-Q value, which is measured to be unprecedented at 700. The resulting improvement in the Cerenkov lasing efficiency is estimated to be more than two orders of magnitude using a particle-in-cell simulation.

Journal of Electromagnetic Waves and Applications, 2017

The field emission properties of the controlled emission edge of a vertically aligned graphene-ba... more The field emission properties of the controlled emission edge of a vertically aligned graphene-based thin film are presented. A current and current density of above 7 mA and 200 A/cm 2 , respectively, with uniform electron emission, are achieved. Uniform high current and current density emissions can be realized by the pre-mechanical shaping and post electrical conditioning of reduced graphene oxide (rGO) film emission, owing to the robustness, thinness (<1 μm), and well-defined uniform film thickness. Field emission luminance demonstrates uniform emission over the entire emission area with a high aspect ratio. Along with a high current emission, the rGO film exhibits excellent emission stability, long-term. This offers prospects for various applications in field emission displays, electron microscopy, and particularly for the realization of miniaturized terahertz vacuum electronic devices, which require electron sources with uniform high currents and current densities, such as long-lifetime cold cathodes.

2015 40th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz), 2015

The field emission from the edge of vertically aligned reduced graphene oxide (rGO) film was exam... more The field emission from the edge of vertically aligned reduced graphene oxide (rGO) film was examined experimentally. High current (I > 5 mA) and high emission current density (J > 100 A/cm2) was obtained using diode configuration. The thermal runaway of sharp protrusions on emission edge are considered to be source for the destructive vacuum breakdowns due to high local emission current. A remarkable field emission stability was achieved using processed field induced evaporation, by removing the protrusions and recovering the totally field emission attributed I-V characteristics.

The Rare Isotope Science Project (RISP) is an accelerator facility for providing beams of exotic ... more The Rare Isotope Science Project (RISP) is an accelerator facility for providing beams of exotic rare isotopes of various energies. The RISP driver linac that accelerates the beam utilizes variety of low-beta superconductive RF cavities with different dimension and frequencies. Low-β cavities are just cavities that accelerate efficiently particles with velocity β < 1. Low-β cavities have many different shapes, sizes and EM modes to allow for a rather large variety of beams that differ in velocity, intensity and A/q. Important differences from elliptical cavities are also the higher peak surface fields Epeak and Bpeak required to get the same acceleration, and the lower RF frequency. A typical superconducting low-β linac consists of many short cavities, independently powered and phased, with a small number of gaps (typically 2 or 3) and relatively large aperture compared to normal conducting ones. In this paper, we present the electromagnetic optimization of quarter-wave, half-wav...

This abstract describes the design, fabrication and testing of microfabricated 0.1 THz coupled-ca... more This abstract describes the design, fabrication and testing of microfabricated 0.1 THz coupled-cavity backward wave oscillator, which is operated in spatial harmonics -1 at beam voltage 12 kV, current 50 mA, cylindrical beam minimum radius 0.18 mm and required axial brillouin field > 1 kG . The RF performance has studied using 3-D electromagnetic field simulator and particle-in-cell code. The simulated output power is more than 4 W (~ 1 % electronic efficiency) because of choosing low voltage operation in spatial harmonics -1 with considering the thermal and structural issues in discussed device. The complete device assembly for beam-test and RF-test is being fabricated. Experimental results will be presented

2007 IEEE International Vacuum Electronics Conference, 2007

The experimental study on electron guns with high current density beam for THz devices is carried... more The experimental study on electron guns with high current density beam for THz devices is carried out. A thermionic electron gun is designed and the fabrication is underway. The current density requirement at the circuit is &amp;amp;amp;amp;amp;gt;50 A/cm2 for 0.1 THz LIGA fabricated devices [1]. A rectangular sheet electron beam for 0.5THz needs to meet the beam current density requirement

2013 IEEE 14th International Vacuum Electronics Conference (IVEC), 2013

ABSTRACT Effective electromagnetic coupling with electronic equipment at radiation is used by a h... more ABSTRACT Effective electromagnetic coupling with electronic equipment at radiation is used by a high power microwave (HPM) weapons source which means a relativistic backward wave oscillator in here. In the process of researching, developing and using HPM source, we have been studying a real “effective coupling” source which is able to attack the overall target, suitable in all situation ns. The experimental results show the broken electronic equipment or circuit damages after the radiation by an X-band relativistic backward wave oscillator (RBWO) of a HPM source with mode conversion. We used 500kA-5kA RBWO. The RF power is 0.5GW-30ns at 10GHz with mode conversion radiation from TM01 to TE11.

2012 37th International Conference on Infrared, Millimeter, and Terahertz Waves, 2012

ABSTRACT The Smith-Purcell radiation (SPR) in metallic metamaterial grating is studied theoretica... more ABSTRACT The Smith-Purcell radiation (SPR) in metallic metamaterial grating is studied theoretically. This metallic metamaterial is a one-dimensional array of slits with sub-wavelength period perforated on a perfect metallic film, which supports discrete guided modes in presence of convective electron bunch near its surface. It is also found that SPR intensity is enhanced when guided modes couple with diffraction mode. The comparison with lamellar grating shows that the metamaterial grating is more effective converter of evanescent field associates with running charge into radiation. This structure would be promising to develop intense narrow-band Smith-Purcell radiation based THz sources.