A Compact, High-power Terahertz Amplifier for DNP-NMR and EPR Spectroscopy

用于 DNP-NMR 和 EPR 光谱分析的紧凑型高功率太赫兹放大器

• 批准号: 8714444
• 负责人: Jagadishwar Rao Sirigiri
• 金额: $ 21.06万
• 依托单位: BRIDGE 12 TECHNOLOGIES, INC.
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8714444
• 关键词: Address; Amplifiers; Amyloid Fibrils; Analytical Chemistry; Area; Biological; California; Communities; Computers; Copper; Development; Devices; Dimensions; Electron Beam; Electron Spin Resonance Spectroscopy; Electrons; Frequencies; Funding; Future; Gases; Guns; Helium; Image; Individual; Lead; Magic; Measures; Membrane Proteins; Methods; Microfabrication; NMR Spectroscopy; Nuclear; Nuclear Magnetic Resonance; Outcome; Output; Performance; Pharmaceutical Chemistry; Phase; Physiologic pulse; Platelet Factor 4; Price; Process; Research; Research Personnel; Signal Transduction; Solid; Solutions; Source; Structure; Surface; System; Techniques; Technology; Testing; Three-Dimensional Imaging; Time; Travel; Tube; United States National Institutes of Health; biological systems; cold temperature; cost; cost effective; data acquisition; design; detector; electrical property; flexibility; human disease; improved; innovation; interest; macromolecule; magnetic field; microwave electromagnetic radiation; nano; novel; operation; prototype; public health relevance; research study; scale up; solid solution; solid state; solid state nuclear magnetic resonance; structural biology; success; transmission process; vector

DESCRIPTION (provided by applicant): We propose to develop a compact, cost-effective Traveling Wave Tube (TWT) amplifier at 263 GHz with 50 W of peak power, 5 W of continuous wave power and 5% instantaneous bandwidth for application in Dynamic Nuclear Polarization (DNP) enhanced solid-state and solution-state NMR and Electron Paramagnetic Resonance (EPR) spectroscopy. With DNP, the inherently small signal intensities in a NMR experiment can be enhanced by up to two orders of magnitude. This significantly increased overall sensitivity will be highly beneficial for analytical applications of NMR spectroscopy as well as in the structure determination of bio- macromolecules using NMR methods. Currently, DNP is performed with either low power solid-state sources (whose output power is limited to a few mW at frequencies >300 GHz) and at low temperatures in the range of 20-30 K (to compensate for low microwave power) or with large, gyrotron systems which can generate 50 W of power. Gyrotrons are expensive and do not possess sufficient tuning bandwidth (<0.1%) necessary for investigating a wide range of DNP experiments and thus require expensive sweep coils in the NMR magnets. The proposed TWT will address all the above concerns. The TWT can also be used as an external amplifier on a commercial 263 GHz EPR spectrometer to significantly improve the output power capability by 30dB. The TWT is expected to cost less than one-fourth of the cost of a gyrotron system, provide 5% instantaneous bandwidth and will be a compact table-top system. These advantages will allow a larger number of researchers to take advantage of the sensitivity boost offered by DNP in NMR experiments. In Phase I, we will design, build and test key subsystems of the of the TWT including the electron gun, the compact permanent magnet system and the interaction structure. The latter will be built on a state-of-the-art nano-computer numerical controlled (CNC) milling machine to achieve the high precision and surface quality necessary for operation at such high frequencies. The successful testing of the key subsystems will enable optimization of the design for a full prototype in Phase II. The technology is scalable and can be used at frequencies as high as 593 GHz (900 MHz NMR). A higher peak power version of the device will advance the state-of-the-art in high field EPR spectroscopy. As an ultimate result of this project, we expect Bridge12 to offer commercial TWTs from 263 GHz(400 MHz NMR) to 593 GHz (900 MHz NMR) for DNP-NMR and EPR spectroscopy. This will greatly accelerate structure determination of bio-macromolecules of relevance to human disease research funded by NIH.

描述（由申请人提供）：我们建议开发一款紧凑、经济高效的 263 GHz 行波管 (TWT) 放大器，具有 50 W 峰值功率、5 W 连续波功率和 5% 瞬时带宽，用于动态核极化 (DNP) 增强固态和溶液态 NMR 和电子顺磁共振 (EPR) 光谱。使用 DNP，NMR 实验中固有的小信号强度可增强多达两个数量级。总体灵敏度的显着提高将非常有利于核磁共振波谱的分析应用以及使用核磁共振方法测定生物大分子的结构。目前，DNP 要么使用低功率固态源（其输出功率在频率 >300 GHz 时限制为几毫瓦）并在 20-30 K 范围内的低温下执行（以补偿低微波功率），要么使用可产生 50 W 功率的大型回旋管系统。回旋管价格​​昂贵，并且不具备研究各种 DNP 实验所需的足够调谐带宽 (<0.1%)，因此 NMR 磁体中需要昂贵的扫描线圈。拟议的 TWT 将解决上述所有问题。 TWT 还可用作商用 263 GHz EPR 光谱仪的外部放大器，将输出功率能力显着提高 30dB。 TWT 预计成本不到回旋管系统成本的四分之一，提供 5% 的瞬时带宽，并且将是一个紧凑的桌面系统。这些优势将使更多的研究人员能够在 NMR 实验中利用 DNP 提供的灵敏度提升。第一阶段，我们将设计、建造和测试行波管的关键子系统，包括电子枪、紧凑型永磁体系统和相互作用结构。后者将建立在最先进的纳米计算机数控（CNC）铣床上，以实现在如此高的频率下运行所需的高精度和表面质量。关键子系统的成功测试将使第二阶段完整原型的设计得以优化。该技术具有可扩展性，可在高达 593 GHz (900 MHz NMR) 的频率下使用。该设备的更高峰值功率版本将推动高场 EPR 光谱技术的发展。作为该项目的最终成果，我们预计 Bridge12 将为 DNP-NMR 和 EPR 光谱提供从 263 GHz（400 MHz NMR）到 593 GHz（900 MHz NMR）的商用行波管。这将大大加速与 NIH 资助的人类疾病研究相关的生物大分子的结构测定。