<i>Q</i>-band loop-gap resonator

Abstract

The upper frequency for loop-gap resonators intended for use in electron-spin-resonance spectroscopy has been extended to Q band (35 GHz). A practical structure is described containing sample support, frequency tuning, and variable coupling. A typical sample volume is 39 nL. High-energy densities (15 GW−1/2) were achieved. As found previously at X band, Q-band loop-gap resonators permit observation of the dispersion with minimal demodulation of phase noise originating in the klystron. Theoretical calculations of the resonant frequency, Q, and the filling factor are found to be in good agreement with experiment.