Theoretical analysis on the beam-wave interaction of a THz gyrotron oscillator

Ashutosh Singh
Department of Physics, Mahesh Prasad Sinha Science College,
Babasaheb Bhimrao Ambedkar Bihar University, Muzaffarpur-843 146, Bihar, India.
This paper is dedicated to Dr Shrinivas Joshi

The beam-wave interaction behavior of a 670 GHz gyrotron operating in the TE_25,10 mode is presented using nonlinear time-dependent multimode theory. The conventional cylindrical cavity is used to study the RF behavior of this THz gyrotron oscillator. The effects of mode competition are also studied for such a high-frequency and higher-order operating mode gyrotron. The selection of modes and electron beam parameters are estimated using single-mode analysis. The phase and momentum of electrons along the interaction length of the cavity are presented for realizing energy transfer phenomena from the electron beam to RF. The output power for the designed TE_25,10 mode as well as all nearby competing modes has been estimated and the output power of about 265 kW with ~27% electronic efficiency is observed in the designed mode, while all other competing modes have significantly low output power for the optimized device parameters. The effect of electron beam parameters on the device performance is also studied. The present study is expected to be useful for designing the THz gyrotron operating in pulsed mode of several milliseconds for detection of radioactive materials. © Anita Publications. All rights reserved.
Doi: 10.54955/AJP.33.9-10.2024.575-582
Keywords: Beam-wave interaction, Gyrotron oscillator, Multimode theory, THz device.

Peer Review Information
Method: Single- anonymous; Screened for Plagiarism? Yes
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