- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Stress Test of Nanosecond Semiconductor Cavity Switches with Subterahertz Gyrotrons
摘要： Nanosecond semiconductor switches based on resonant cavity with reversibly variable Q-factor are the most prospective devices for generating unlimited series of coherent pulses in subterahertz frequency bands. The pulse duration stretches from nanoseconds to tens of seconds for the same device. While the subterahertz switches have already been tested with various continuous-wave generators, e.g. semiconductor transistors and backwards wave oscillators, they are intended to be used with gyrotrons, the most powerful generators of coherent microwave radiation for subterahertz bands. Here we present results of several experiments with continuous wave (CW) and pulsed gyrotrons with frequencies around 300 GHz, pulse durations up to 10 s, and stressful microwave power up to 180 kW. A simple generalized theoretical estimation for the microwave power limit of the switches is provided and found to be in a good agreement with the performed experiments, avoiding blind zones in subterahertz measurements.
关键词： lasers,switches,waveguides,gyrotrons,Semiconductor devices,microwave resonators,generation,optical switches
更新于2025-09-19 17:15:36
-
Generation of rogue waves in gyrotrons with high excess over the threshold
摘要： Many physical systems exhibit behavior associated with the emergence of the so-called rogue waves which represent dramatically high-amplitude events that occur with low probability but much more frequently than expected in ordinary wave statistics [1]. For example, in laser physics and optics rogue waves arise in the process of supercontinuum generation and represent pulses of ultra broadband light with extremely high peak power [2]. In this paper within the framework of the average approach and in direct 3D PIC (particle-in-cell) simulations we demonstrate that rogue waves can also appear in gyrotrons operating with high excess over the threshold. The mechanism of extreme spikes formation is related to simultaneous cyclotron interaction of a gyrating electron beam with forward and backward waves near the waveguide cutoff frequency as well as with the longitudinal deceleration of electrons. From the practical point of view, experimental observation of the rogue waves generation in gyrotrons can be interesting as a method for production of high-power millimeter-wave radiation with an ultra broadband spectrum. The required exceeding over the threshold can be achieved for routine parameters of the driving electron beams formed by the magnetron-injection guns due to operation at the lowest modes of microwave cavities.
关键词： high-power millimeter-wave radiation,rogue waves,gyrotrons,ultra broadband spectrum
更新于2025-09-10 09:29:36
-
[IEEE 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz2018) - Nagoya, Japan (2018.9.9-2018.9.14)] 2018 43rd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) - Terahertz Gyrotrons with Unique Parameters
摘要： Development of high power THz sources play important role for development advance technologies in physics, chemistry, biology, medicine. The main goal of this report is present together data about gyrotron development and the most striking examples of modern applications. The paper describes some features of THz tubes. The key information about pulsed and CW tubes is given. The described gyrotrons demonstrate (in some specific combinations) extremely low voltage and beam current, narrow frequency spectrum, wide range frequency tuning. Novel schemes of high frequency gyrotrons are analyzed. Examples of gyrotron based experiments for spectroscopy, data transmission and localized gas discharge are presented.
关键词： spectroscopy,data transmission,THz sources,gyrotrons,gas discharge
更新于2025-09-09 09:28:46