太赫兹回旋管蓝宝石输能窗的设计及实验

Design and experimental research of a terahertz-gyrotron output window with sapphire disc

摘要:

针对170 GHz兆瓦级回旋管短脉冲实验对蓝宝石输能窗的实际要求，分析了蓝宝石窗传输高斯波束的反射和吸收特性，优化设计了低反射、低损耗蓝宝石输能窗的工程方案。对研制的蓝宝石窗部件进行微波冷测，驻波比(VSWR)小于1.1，验证了蓝宝石窗的低反射特性；计算结果表明该结构的最大输出平均功率阈值为590 W。对使用该蓝宝石窗研制的170 GHz回旋管进行测试，验证了理论计算的功率阈值，为大功率回旋管蓝宝石输能窗的实际应用提供了依据。

Abstract:

To satisfy the application requirements of sapphire output window for the 170 GHz megawatt-class gyrotron short-pulsed experiment, by calculating the characteristic of reflection and absorbing of Gaussian beam transmitted through sapphire window, a sapphire window unit is designed with low reflection and low loss power. The low reflectance is verified by vector network analyzer that the Voltage Standing Wave Ratio(VSWR)<1.1. The maximum output average power threshold of the sapphire window has been calculated approximately to be 590 W by analyzing the damage mechanism. The 170 GHz gyrotron employing sapphire window is fabricated, and the power threshold calculated theoretically is verified, providing a reliable theoretical basis for the application of sapphire output window used in high power gyrotron.