中国激光, 2019, 46 (6): 0614001, 网络出版: 2019-06-14
应用于动态核极化核磁共振的太赫兹回旋管 下载: 1157次
Terahertz Gyrotron Used for Dynamic Nuclear-Polarization-Enhanced Nuclear Magnetic Resonance
太赫兹 频率连续可调回旋管 多段式腔体结构 电子注质量 terahertz frequency-tunable gyrotron muti-section cavity electron beam quality
摘要
太赫兹波驱动的动态核极化核磁共振波谱技术能将信号灵敏度提高几个数量级,太赫兹回旋管可实现高功率输出,并有一定的频率调谐范围,符合核磁共振波谱系统对太赫兹辐射源的需求。介绍了应用于核磁共振波谱系统的频率可调太赫兹回旋管的发展,研究了多段式腔体结构以及频率可调太赫兹回旋管中工作电压和磁场与电子注质量的关系。在应用于动态核极化核磁共振的太赫兹频率可调回旋管工作时,多段式腔体结构明显优于传统三段式谐振腔。在设计太赫兹频率可调回旋管时,不仅要考虑改变工作电压或磁场导致的电子横纵速度比的变化,而且还要考虑改变工作电压或磁场导致的电子速度离散和引导中心半径离散的变化。
Abstract
The technology of terahertz wave-driven dynamic nuclear-polarization-enhanced nuclear magnetic resonance (DNP-NMR) spectroscopy can improve signal sensitivity by several orders of magnitude. The terahertz gyrotron can realize a high power output and has a certain frequency-tunable range, which meets the terahertz radiation source requirements of a NMR spectroscopic system. Herein, the development of a frequency-tunable terahertz gyrotron used for the DNP-NMR spectroscopic system was introduced. The structure of a multi-section gyrotron cavity and the variation of the electron beam quality in the frequency-tunable terahertz gyrotron with the operating voltage and the operating magnetic field were also investigated. The results show that the multi-section cavity is better than the conventional three-section cavity when the terahertz frequency-tunable gyrotron used for the DNP-NMR is operating. In the design of a frequency-tunable terahertz gyrotron, not only the variation of the velocity pitch factor but also the variation of the velocity spread and the guiding center radius spread of the electron beam related to the operating voltage or the operating magnetic field should be taken into account.
宋韬, 王维, 刘頔威, 刘盛纲. 应用于动态核极化核磁共振的太赫兹回旋管[J]. 中国激光, 2019, 46(6): 0614001. Tao Song, Wei Wang, Diwei Liu, Shenggang Liu. Terahertz Gyrotron Used for Dynamic Nuclear-Polarization-Enhanced Nuclear Magnetic Resonance[J]. Chinese Journal of Lasers, 2019, 46(6): 0614001.