A High Power, Broadband 395 GHz Gyrotron Amplifier for DNP-NMR and EPR Spectroscopy

项目总结/摘要 我们提出了一种新型的陀螺行波管放大器（gyro-TWT）在395 GHz的输出 功率为500 W，工作带宽超过3 GHz，小信号增益> 45 dB。放大器 将用于动态核极化（DNP）增强核磁共振（DNP-NMR） 实验和电子顺磁共振（EPR）实验。建议的输出功率 放大器是三个订单大于那些可从固态源在类似的频率和 工作带宽与相干放大用于DNP-NMR的复数输入信号的能力相结合 和EPR将使新一代的脉冲DNP-NMR和EPR实验，目前不可能 以利用自由运行的固定频率振荡器来执行。这种放大器可以升级目前部署的 几十个回旋振荡器用于DNP-NMR，并为研究人员提供了进行 实验与广泛的极化剂，而不需要超导扫描线圈在 核磁共振磁铁。此外，放大器将使研究人员能够探索脉冲DNP-NMR的前景 实验该放大器的峰值功率为500 W，占空比为10%或10%。 连续波模式，输出功率为50 W。 在第一阶段，我们将设计放大器系统，并对其进行详细的建模和仿真。 使用微波管研究中使用的基准最先进的设计代码来评估性能。我们将 提出系统的完整机械设计，并使用 商用有限元程序我们还将建立和测试最重要的冷性能 元件的系统，即相互作用电路，并证明其适合集成的 管材.这些测试将在矢量网络分析仪上进行，以验证微波传播 设备的属性。在第二阶段，我们将制作电子枪，内模转换器和其他 辅助部件，如微波窗口等。整个系统将在我们的 实验室来证明拟议的输出功率和带宽。

Project Summary / Abstract We propose to develop a novel gyro traveling wave tube amplifier (gyro-TWT) at 395 GHz with an output power of 500 W and an operating bandwidth exceeding 3 GHz and a small signal gain > 45 dB. The amplifier will be used in Dynamic Nuclear Polarization (DNP) enhanced Nuclear Magnetic Resonance (DNP-NMR) experiments and Electron Paramagnetic Resonance (EPR) experiments. The output power of the proposed amplifier is three orders greater than those available from solid-state sources at similar frequencies and the operating bandwidth combined with the ability to coherently amplify complex input signals for use in DNP-NMR and EPR will enable new generation of pulsed DNP-NMR and EPR experiments that are currently impossible to perform with free running fixed frequency oscillators. This amplifier can upgrade the currently deployed dozens of gyrotron oscillators for use in DNP-NMR and provide researchers with the ability of conducting experiments with a broad range of polarizing agents without the need for a superconducting sweep coils in the NMR magnet. Also, the amplifier will enable researchers to explore the promise of pulsed DNP-NMR experiments. The proposed amplifier can be operated with a peak power 500 W with a duty factor of 10 % or in continuous wave mode with an output power of 50 W. In Phase I, we will design the amplifier system and perform detailed modeling and simulation of its performance using benchmarked state-of-the-art design codes used in microwave tube research. We will present a complete mechanical design of the system and verify the thermal and electrical properties using commercial finite element codes. We will also build and test the cold performance of the most important element of the system, namely, the interaction circuit and demonstrate its suitability for integration with the tube. These tests will be performed on a Vector Network Analyzer to verify the microwave propagation properties of the device. In Phase II, we will fabricate the electron gun, the internal mode converter and other auxiliary components such as microwave windows etc. The entire system will be integrated and tested in our laboratory to demonstrate the proposed output power and bandwidth.