The gyrotron includes a sealed custom-designed gyrotron tube, superconducting magnet, and control system, all designed to provide high stability, reliability, and ease of operation. Beam propagation to the sample is ensured by high microwave beam quality and corrugated waveguide. The sample is polarized in-situ in a low-temperature NMR MAS probe.
The 263 GHz klystron is a continuous-wave microwave source designed and manufactured for extended DNP NMR at 400 MHz 1H frequency and 100 K sample temperature. The klystron provides a DNP option with lower purchase price, operating costs, footprint, and facility requirements compared to the gyrotron product line while retaining high DNP sensitivity and stability. At 5 W output power, it reaches 90-100% DNP efficiency on biological samples and small molecules in frozen solution while dense material samples perform at > 80% compared to the 263 GHz gyrotron.
The system assembly consists of: (1) extended interaction klystron oscillator (EIK), (2) a control system with graphical user interface, safety interlocks, power supply and cooling network, and (3) a low-loss microwave transmission line. It is compatible with a 400 WB Ascend DNP solid-state NMR spectrometer and Bruker low-temperature MAS (LTMAS) probes.