摘要： The nonstationary oscillation of the gyrotron backward wave oscillator (gyro-BWO) with cylindrical interaction structure was studied utilizing both steady-state analyses and time-dependent simulations. Comparisons of the numerical results reveal that the gyro-BWO becomes nonstationary when the trailing field structure completely forms due to the dephasing energetic electrons. The backward propagation of radiated waves with a lower resonant frequency from the trailing field structure interferes with the main internal feedback loop, thereby inducing the nonstationary oscillation of the gyro-BWO. The nonstationary gyro-BWO exhibits the same spectral pattern of modulated oscillations with a constant frequency separation between the central frequency and sidebands throughout the whole system. The frequency separation is found to be scaled with the square root of the maximum field amplitude, thus further demonstrating that the nonstationary oscillation of the gyro-BWO is associated with the beam-wave resonance detuning. 出版者： Melville: American Institute of Physics 出版日期： 2013-12-01 出處： Physics of plasmas, 2013-12, Vol.20 (12) 資源來源： AIP Journals (American Institute of Physics) 版權： 2013 AIP Publishing LLC. 識別號： ISSN: 1070-664X 識別號： EISSN: 1089-7674 識別號： DOI: 10.1063/1.4846876
