DEVELOPMENT OF TERAHERTZ GYROTRON AND ITS APPLICATION TO PLASMA SCATTERING MEASUREMENT

在本项目中，我们开发了频率可调、中功率、亚毫米波回旋管，并将其应用于国家聚变科学研究所CHS等离子体的亚毫米波散射测量。研究结果如下：1)利用12T和17T超导磁体，研制出频率接近1太赫兹的超高频回旋管。我们已经达到了847 GHz的最高频率。这个频率是回旋管高频工作的世界纪录。2)回旋管的连续波工作我们实现了回旋管的完整连续波工作，并成功地实现了回旋管输出振幅和频率的稳定，以便将回旋管作为辐射源应用于亚毫米波光谱。3)亚毫米波回旋管输出的幅度和频率调制我们实现了回旋管输出的幅度和频率调制，使其应用于更广泛的领域。4)基频与次谐波模式竞争与模式合作的研究5)亚毫米波回旋管输出准光传输系统的研制6)毫米波高灵敏度探测器的研制。以亚毫米波回旋管为辐射源的等离子体散射测量我们将自己研制的亚毫米波散射测量系统（gyrotron FU II）作为辐射源应用于国家聚变科学研究所的CHS，并成功测量了装置中自发激发的漂移波。大功率远红外激光器的研制及其在等离子体散射测量中的应用回旋管毫米波ESR的研究

In this project, we have developed frequency-tunable, medium power, submillimeter wave gyrotrons and applied them to submillimeter wave sacattering measurement of CHS plasma in National Institute for Fusion Science. Research results are summarized as follows,1) Ultra-high frequency operation of gyrotron by the second and the third harmonics Using 12T and 17T superconducting magnets, we developed high frequency gyrotrons whose frequensies are close to 1 terahertz. We have achieved the highest frequency of 847 GHz. This frequency is the world record of high frequency operation of gyrotron.2) cw operation of gyrotronWe have realized complete cw operation of the gyrotron and succeeded to achieve stabilities of amplitude and frequency of the gyrotron output, in order to apply the gyrotron to submillimeter wave spectroscopy as radiation source.3) Amplitude and frequency modulations of the submillimeter wave gyrotron output We have achived amplitude and frequency modulations of the gyrotron output for its application to wider fields.4) Studies on mode competition and mode cooperation between the fundamental and the second harmonic operations5) Development of quasi-optical transmission system for submillimeter wave gyrotrons outputs6) Development of a high sensitive detector in a millimeter wave range using a high T。 superconductor7) Plasma scattering measurement using a submillimeter wave gyrotron as a radiation sourceWe have applied the submillimeter wave scattering measurement system using our gyrotron (GYROTRON FU II) as a radiation source for CHS in National Institute for fUsion Science and succeeded in measurement of drift wave excited spontaneously in the device.8) Development of a high power, far-infrared laser and its application to plasma scattering measurement9) Study on the millimeterr wave ESR using a gyrotron as a radiation source