Yoh Matsuki, Keisuke Ueda
In this paper we present results that demonstrate the utility of a continuously frequency-tunable 0.4 THz-gyrotron in a dynamic nuclear polarization (DNP)-enhanced solid-state NMR (SSNMR) spectroscopy at one of the highest magnetic fields, 14.1 T (600 MHz for 1H Larmor frequency). Our gyrotron called FU CW VI generates sub-mm wave at a frequency near 0.4 THz with an output power of 4–25 W and a tunability over a range of more than 1 GHz by sweeping the magnetic field at the gyrotron cavity. We observed overall down shifting of the central frequency by up to ~1 GHz at high radiation duty factors and beam current, presumably due to the cavity thermal expansion by a heating, but the tunable range was not significantly changed. The frequency tunability facilitated the optimization of the DNP resonance condition without time-consuming field-sweep of the high-resolution NMR magnet, and enabled us to observe substantial enhancement of the SSNMR signal (εDNP012 at 90 K).
@article{035cb4f1-a005-4f80-bf56-eeb579aec3e3,
title={Application of Continuously Frequency Tu},
author={Yoh Matsuki and Keisuke Ueda},
year={2026},
language={en}
}TY - JOUR TI - Application of Continuously Frequency Tu AU - Yoh Matsuki AU - Keisuke Ueda PY - 2026 LA - en ER -
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