Low Noise Coupling and Signal Detection for EPR Spectroscopy

新谐振结构和现代微波技术在材料科学、化学、物理、生物和医学等问题的EPR研究中的应用，由于缺乏工程设计数据而受到限制。PI建议测试我们对电感耦合、并联电容耦合和串联电容耦合的理论结果的定量预测。将探讨耦合对尺寸和电气参数的敏感性。最佳设计将用于连续波和脉冲s波段和X波段光谱仪。主要的焦点将是样品的变化，返回，和可变温度操作的样品包含在标准圆柱形管和各种介电常数的溶剂。各种各样的设备将被建造：一个混合微波EPR桥，它将比现有的桥更敏感，更经济。用于s波段操作的电子可调谐LGR，将提高谐振器/匹配网络的可调谐性。一种系统，其中前置放大器与谐振器一起冷却，以利用在低温下可能的低噪声。许多研究小组迫切需要来自提议工作的设计指导。研究结果将提高美国光谱测量的竞争力。

The application of promising new resonant structures and modern microwave technology to EPR studies of problems in materials science, chemistry, physics, biology, and medicine, is limited by the lack of engineering design data. The PI's propose to test the quantitative predictions of our theoretical results for inductive coupling, parallel capacitive coupling, and series capacitive coupling. Sensitivity of coupling to dimensional and electrical parameters will be explored. The best designs will be implemented for CW and pulsed S-band and X- band spectrometers. Primary focus will be on ease of sample change, returning, and variable temperature operation for samples contained in standard cylindrical tubes and in solvents of various dielectric constants. A variety of equipment will be built: A hybrid microwave EPR bridge that will be more sensitive and cost-effective than present bridges. An electronically tunable LGR for S-band operation that will improve tunability of the resonator/matching network. A system in which the preamplifier is cooled along with the resonator to take advantage of the low noise possible at cryogenic temperature. Design guidance that will come from the proposed work is urgently needed by many research groups. The results will enhance the competitiveness of American spectroscopic measurements.