Demonstration of a 263 GHz gyrotron for Dynamic Nuclear Polarization

Dynamic Nuclear Polarization (DNP) can be used to increase the sensitivity of nuclear magnetic resonance (NMR) experiments by transferring the much higher polarization of unpaired electrons spins to nuclear spins. The polarization transfer is driven by high frequency millimeter wave irradiation. Communications and Power Industries is an original equipment manufacturer of gyrotron tubes for Bruker Biospin's 263 GHz DNP spectrometer, which is used with a 400 MHz NMR system. The key components of the DNP system include a cw gyrotron tube operating near 263 GHz at power levels of 25 W, nominally, a 9.7 T superconducting magnet, a power supply and control system, a transmission line from the gyrotron to the NMR sample, and a low-temperature magnetic-angle-spinning probe.