Effects of microwave frequency on the growth rate of upstream dielectric mulatipactor are studied. Our previous research [Plasma Sources Sci. Technol. 27 (2018) 125006] shows that the growth rate is independent of microwave frequency in a strong microwave. However, this note shows that the growth rate would decrease quickly to a negative value if the microwave frequency increases to be above a critical value (far away from the first crossover point of unit secondary yield). This phenomenon is observed by electromagnetic particle-in-cell simulation on a dielectric exposed to microwaves of TEM mode, TE01 mode, and TE11 mode, respectively. Consistent simulation results and theoretical results show that the suppression of multipactor is induced from the returning difficulty of emitted electrons, and the critical microwave frequency corresponding to zero growth rate is in direct proportion to the rf electric field amplitude and is in positive correlation with the secondary electron yield.

中文翻译：

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微波频率对上游介质多路复用器生长速率的影响

研究了微波频率对上游介质多路复用器生长速率的影响。我们之前的研究 [Plasma Sources Sci. 技术。27 (2018) 125006] 表明，在强微波中，生长速率与微波频率无关。但是，该注释表明，如果微波频率增加到高于临界值（远离单位二次产量的第一个交叉点），则增长率将迅速下降到负值。这种现象是通过对暴露于 TEM 模式、TE01 模式和 TE11 模式微波的电介质进行电磁粒子内模拟观察到的。一致的模拟结果和理论结果表明，多粒子的抑制是由发射电子的返回困难引起的，