Tuesday, February 28, 2017
Abstract: A 140 GHz pulsed gyro-amplifier system is under development for applications to Dynamic Nuclear Polarization NMR. We discuss the theory, design, and experimental results of this gyro-amplifier system. The gyro-amplifier uses a sever-less, confocal geometry to provide and overmoded interaction circuit with reduced mode competition. High gain is achieved by including ceramic absorbers in order at attenuate unwanted oscillations due to spatial modes that are reflected from the outer vacuum tube wall. The system is estimated to have achieved 35 dB of circuit gain using a 46 kV, 3 A electron beam.