Investigation of subterahertz gyrotron for DNP NMR spectroscopy at IAP RAS

The present paper concerns the state of the art of the development and experimental investigations of subterahertz gyrotrons for spectroscopy applications at IAP RAS. The gyrotron with frequency of 258 GHz and power of 100 watts is successfully used for spectroscopy experiments and 80-time rising of sensitivity has been obtained. The fundamental harmonic gyrotron with an internal mode converter is under development now. The predicted efficiency is 20% at power about 100 W and frequency of 263 GHz. The same helium-free 10-T magnet and electron optics will be used for design of a second harmonic tube with operating frequency of 520 GHz.