Tunable 330 GHz Gyrotron for DNP/NMR

用于 DNP/NMR 的可调谐 330 GHz 回旋管

• 批准号: 7178519
• 负责人: RICHARD J TEMKIN
• 金额: $ 43.77万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-07 至 2009-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7178519
• 关键词: Complex; Condition; Coupling; Detection; Development; Electronics; Freezing; Frequencies; Hand; Laboratories; Magnetism; Mechanics; Methods; Noise; Nuclear; Numbers; Principal Investigator; Range; Research; Sampling; Science; Signal Transduction; Solutions; Source; System; Techniques; Temperature; Vacuum; Variant; base; cold temperature; cost; design; instrumentation; magnetic field; melting; microwave electromagnetic radiation; nitroxyl; novel; programs; research study; size; solid state; voltage

DESCRIPTION (provided by applicant): We propose a program of research to design, build and operate a tunable 330 GHz gyrotron oscillator for CW DNP/NMR research. There are a number of 500/89 magnets in solid-state NMR laboratories around the world and these could be used with a 330 GHz microwave source to perform DNP/NMR. However, all of the known DNP mechanisms require that the magnetic field be adjusted to the peak of the enhancement curve to optimize the signal to noise ratio (S/N) of the experiment. This necessitates either that the magnetic field be swept with a sweep coil on the magnet, or that the microwave frequency be adjusted. In NMR systems using magnets with sweep coils, DNP/NMR research can be conducted with fixed frequency gyrotrons. However, the vast majority of NMR magnets in existence do not have sweep coils and it is impractical to retrofit these systems. Therefore, a tunable gyrotron oscillator appears to be the approach of choice for laboratories with this type of magnet. We propose to design and fabricate a 330 GHz gyrotron that can be tuned over a range of ¿0.75 GHz which will permit coverage, for example, of the TEMPO EPR spectrum where the peaks in the enhancement curve will be separated by about 710 MHz. The tunable gyrotron oscillator will utilize a novel magnetic field tuning approach based on the excitation of high order axial modes of the resonator. Frequency tuning of ¿0.9 GHz has been recently demonstrated on a 250 GHz gyrotron oscillator here at MIT. The gyrotron design will, in principle, be scalable to higher frequencies for application to 600 to 900 MHz where wide-bore magnets are currently available.

描述（由申请人提供）：我们提出了一项研究计划，旨在设计、构建和操作用于 CW DNP/NMR 研究的可调谐 330 GHz 陀螺振荡器。世界各地的固态 NMR 实验室中有许多 500/89 磁体。这些可以与 330 GHz 微波源一起使用来执行 DNP/NMR 然而，所有已知的 DNP 机制都需要磁场。调整到增强曲线的峰值以优化实验的信噪比（S/N），这需要使用磁体上的扫描线圈扫描磁场，或者调整微波频率。使用带有扫描线圈的磁体的 NMR 系统，DNP/NMR 研究可以使用固定频率回旋管进行，但是，现有的绝大多数 NMR 磁体没有扫描线圈，因此改造这些系统是不切实际的。可调谐陀螺仪振荡器似乎是使用此类磁铁的实验室的首选方法，我们建议设计和制造可在 ¿ 范围内调谐的 330 GHz 陀螺仪。例如，0.75 GHz 可以覆盖 TEMPO EPR 频谱，其中增强曲线中的峰值将相隔约 710 MHz。可调谐陀螺振荡器将采用基于高阶轴向激励的新型磁场调谐方法。谐振器的频率调谐。最近，麻省理工学院在 250 GHz 陀螺仪振荡器上演示了 0.9 GHz。原则上，该陀螺仪设计可扩展到更高的频率，适用于目前可使用宽孔磁体的 600 至 900 MHz 频率。