Investigations of RF behavior of a sub-terahertz gyrotron for DNP-NMR application

Vishal Singh and M Thottappan
Center of Research in Microwave Tubes (CRMT), Department of Electronics Engineering,
Indian Institute of Technology (BHU), Varanasi-221 005. India
This paper is dedicated to Dr Shrinivas Joshi

A nonlinear multimode code was used to investigate the RF behaviour of 330 GHz, second harmonic  mode of cylindrical cavity tunable gyrotron. The time-dependent multimode theory of gyrotron was implemented to study the beam-wave interaction mechanism. The cold cavity behaviour, including the operating mode and frequency, was observed by modelling it in ‘CST Microwave Studio’. The magnetic field profile was kept uniform along the length of the interaction structure. The output power for the designed mode and competing modes have been estimated using the multimode code that predicted it to be 48W with 2.5% electronic efficiency; however, some smaller output power is in the competing modes. © Anita Publications. All rights reserved.
Doi: 10.54955/AJP.33.9-10.2024.633-639
Keywords: DNP-NMR, Gyrotron, Sub-terahertz wave, Cold cavity, Beam-wave interaction, Multimode analysis.

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