Anton A. Burtsev

Modeling a subterahertz traveling-wave tube with a slow-wave structure of the double grating type and a sheet electron beam

A traveling-wave tube of the millimeter range belonging to the short-wavelength region with a sheet electron beam and a slow-wave structure of the double grating type is studied. Its dispersion characteristics and coupling impedances for various spatial harmonics are calculated. The issues of design of the electron-optical system are discussed. The focusing of a sheet electron beam with a high current density by a uniform magnetic field is modeled.

Experimental study of electron guns for TWT of terahertz range

This paper presents the results of experimental testing of diode electron guns with sheet and multiple electron beams based on thermionic minicathodes for TWT of terahertz frequency range. The results of study in pulse mode of impregnated thermionic blade cathode with linear dimensions 0.1×0.7 mm with a current density of 114 A/cm2 are presented. A version of the five-beam electron gun is proposed with cylindrical minicathode with diameter of 0.25 mm, placing under the cells of control grid, achieved a current density of 85.5 A/cm2 at grid voltage of 900-1000 V.

Development of electron-optical system with three elliptic electron beams for a THz-band vacuum-tube device

The results of design, simulation, and experimental testing of an electron-optical system with three elliptic electron beams are presented. Total beam current is 93 mA. The beams are focused by a PPM system with 0.55 T magnitude of the magnetic field. Beam transmission in a rectangular tunnel at over 25 mm distance is demonstrated. The developed electron optical system is assumed to be used in sub-THz-band vacuum-tube devices such as O-type traveling-wave tube or backward-wave oscillator. Electromagnetic parameters of a double-grating staggered slow-wave structure are calculated.

The electron-optical system with magnetic focusing based on sheet carbon nanotube field emitters for twt at terahertz frequencies

This report presents the results of calculation of electron-optical system consisting of a sheet CNT field emission cathode with a microgrid spaced from the surface of the emitter at 100 microns. On the basis of experimental data, it has been designed electron-optical system with a sheet CNT cathode with linear convergence of 6,25, and with the beam current density of 4,46 A/cm2. The thickness of the beam in the interaction space is 0,16 mm. In this case, the simulation of the sheet electron beam, generated by electron gun has shown feasibility of obtaining of low-perveance flow with a small deformation in beam tunnel 0,3×0,8 at 25 mm slow-wave system length.

Forming of high current density sheet electron beams for a sub-THZ TWT vacuum aamplifiers

In this paper we present the computer analysis of magnetic focusing sheet electron beam with low perveance in the electron-optical systems with an electron gun based on thermionic cathode with a current density of 100 A/cm2 at the distance of tunnel 25 mm. The results of experimental study in the diode mode of impregnated thermionic cathode with linear dimensions 0,1 × 0,7 mm have shown the feasibility of using this cathode in sub-THz vacuum amplifiers.

The laminar electron flows in triode electron guns with field emission

3D simulation of triode electron gun is performed with regards its structure of multiple-tip field emission cathode. The table of geometrical parameters of electron gun is defined (d_g-a/D_a=1.5-4.0; d_g-a/d_g-c=10^-4-10^-2) as well as the optimal potentials of grid with large scale holes where the electrical field is uniform. Thus the effect of electron lens of grid comes to a minimum and laminar electron flow is formed. The computer modeling of 19- beam electron gun with field emission glassy carbon cathode in magnetic field (N=10⁶cm^-2) and planar single-beam electron gun with CNT cathode (N=4·10⁸cm^-2) are carried out.

The electron-optical systems with a sheet electron beam of THz band TWT with increased uniformity of magnetic field

This paper presents the results of computer analysis of the sheet electron beams in a uniform and reverse magnetic field for low perveance electron-optical system based on thermionic cathode with a current density of 100 A/cm2 with a total length of 60-65 mm. Experimental studies in diode mode of dispenser thermionic cathode with dimensions of 0,1·0,7 mm are conducted and the feasibility of using one in vacuum microwave amplifiers of terahertz electronics is shown.

The planar field emission array cathodes with carbon nanostructures in twt electron-optical systems

The results of modeling the sub-millimeter TWT electron optical system with a low-voltage control based on the experimental data of the planar array cathode-gate structure with carbon nanostructures are performed in this work. It is shown that the cathode-gate structure including in the analyzed field emission electron gun manufacturing by lithographic processes and CVD technologies may provide the formation a long electron beams with current density of 15,5 A/cm2.

Modeling of planar vane slow wave structures for a travelig wave tube amplifier with sheet electron beam

A fast and accurate code for calculation of eigenwaves in grating slow-wave structures (SWS) is developed. Such SWS are used in sheet-beam traveling wave tubes (TWTs) and backward-wave oscillators (BWOs) at sub-THz and THz frequencies. Results of numerical modeling of SWS for a G-band sheet-beam TWT are presented. Electron gun producing an intensive sheet electron beam s developed. Beam focusing and transportation is discussed.