Progress of a 140 GHz gyro-amplifier using a confocal waveguide

We report on the progress of a 140 GHz, 1 kW pulsed gyro-amplifier system being developed at MIT for enhanced Dynamic Nuclear Polarization for NMR (DNP-NMR). A confo-cal geometry configuration is being studied as an approach to an overmoded interaction waveguide. The gyro-amplifier has achieved 875 W of peak power at 12.5 dB of saturated system gain and 21 dB of linear system gain. Current efforts include optimizing the gyro-amplifier operation, as well as the installation of an internal output mode converter and a corrugated input transmission line system.