A novel multi-pin rectangular waveguide slow-wave structure based backward wave amplifier at 340 GHz

Abstract

A backward wave amplifier (BWA) in a terahertz regime with a novel slow-wave structure (SWS) composed of multi parallel grating pins inside a rectangular waveguide is analyzed. The multi-pin rectangular waveguide SWS possesses good performance and is compatible with micro-fabrication technologies. The dispersion and interaction impedance of the multi-pin SWS are presented. The stopbands of the modes cling together in a Brillouim zone. The SWS has a high interaction impedance that is suitable for the interaction of multi cylindrical beams. The design, which is based on three parallel pins supporting the wave–beam interaction with four cylindrical beams, is verified by three-dimensional particle-in-cell simulations. A BWA with the central frequency at 340 GHz is demonstrated, and the output power is more than 100 mW. A tuning frequency range of 15 GHz (333–348 GHz) is obtained with a gain of more than 20 dB.

Mode Competition of Low Voltage Backward Wave Oscillator near 500 GHz with Parallel Multi-Beam

“…For an amplifier operating at 0.66 THz, the output power is tens of milliwatts when its current density is about 150 A/cm 2 and the focusing magnetic field is about 0.9 T [6]. In 2009, the European Union proposed the OPTHER plan [7] to develop compact and novel vacuum THz radiation sources with a central frequency of 0.987 THz using a carbon nanotube cold cathode required a current density of 795 A/cm 2 and a focusing magnetic field of 0.8 T. Also, some scholars studied a traveling wave tube around 0.3 THz with a current density of about 187 A/cm 2 and a focusing magnetic field of about 0.8 T and the output power about 21 W [8]. However, due to the increase in frequency, the size of vacuum electron devices is getting smaller and smaller and the current density is becoming higher and higher, making its processing and assembly very difficult.…”

Mode analysis and design of 0.3-THz Clinotron

“…In order to develop the potential applications of terahertz waves in space communication, high resolution radar and so on, it is crucial to develop the terahertz source with high output power first. In the low frequency band of terahertz, several kinds of vacuum electronic devices (VEDs) can generate continuous wave or pulsed wave with high output power, [1,2] one of which-Clinotron-has the capability of increasing the beam-wave interaction efficiency and output power as well, [3][4][5][6][7][8][9][10][11][12] showing promising prospects in the development of a terahertz source. The most famous research organization of Clinotron is the National Academy of Sciences (NAS) of Ukraine.…”

A high-power subterahertz surface wave oscillator with separated overmoded slow wave structures

“…[1][2][3] Detecting concealed radioactive materials is also one of the promising applications. [4] For the merits of high efficiency and simple structure, several kinds of vacuum electronic devices have attracted more attention, [5][6][7][8][9][10][11][12][13][14] such as relativistic backward wave oscillator (BWO), multiwave Cerenkov generator (MWCG), and surface wave oscillator (SWO). As one of the promising candidates at high frequencies, the SWO with overmoded structure utilizes an intense electron beam interacting with a surface wave excited in the slow wave structure (SWS) to obtain high-efficiency output and mitigate the fabrication difficulty.…”