We propose a novel source of high-power 1–3-THz radiation based on frequency multiplication in a planar gyrotron, with transverse energy extraction. In such a scheme, it is possible to increase significantly the transverse size both of the cavity and of the electron beam, and, correspondingly, the output power at the fundamental harmonic. At the same time, equidistant mode spectrum of a cavity of planar gyrotrons is favorable for generation at high-order cyclotron harmonics in the frequency multiplication regime, providing a much higher efficiency of nonlinear conversion when compared with conventional cylindrical gyrotron schemes. In simulations of a 1-THz planar gyrotron, within the multimode time-domain model, we demonstrate a possibility of kilowatt-level radiation at the second cyclotron harmonic and power of several watts at the third one. The obtained results are partially confirmed based on direct 3-D particle-in-cell (PIC) simulations.

中文翻译：

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平面回旋管中的倍频作为产生高功率多太赫兹辐射的一种方法

我们提出了一种新的高功率1-3 THz辐射源，该辐射源基于平面回旋管中的倍频并具有横向能量提取。在这样的方案中，可以显着地增大空腔和电子束的横向尺寸，并相应地增大基波谐波处的输出功率。同时，平面回旋管腔的等距模式频谱有利于在倍频方案中以高阶回旋加速器谐波产生，与常规的圆柱回旋管方案相比，提供了更高的非线性转换效率。在多模时域模型内的1-THz平面回旋管的仿真中，我们证明了在第二回旋加速器谐波处产生千瓦级辐射并且在第三回旋加速器处产生几瓦功率的可能性。