DOUBLE-STACKED DIELECTRIC RING RESONATOR FOR EPR MEASUREMENTS OF BIOLOGICAL SAMPLES

M. Jaworski1, A. Sienkiewicz1, C. P. Scholes2

1 Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, 02-668 Warszawa, Poland,
2 Chemistry Department, State University of New York at Albany, 1400 Washington Ave., Albany, NY 12222, U.S.A.


We discuss the microwave properties of a newly developed double-stacked dielectric ring resonator (DR) for applications is Electron Paramagnetic Resonance (EPR) spectroscopy. This design leads to a substantial improvement of the signal-to-noise ratio (S/N), as well as enables one to measure biological samples characterized by high dielectric losses and often limited in supply. The paper presents a new theoretical approach for calculating the resonant frequency, resonator filling factor and resonator Q-factor for the double DR system. The comparison of experimentally and theoretically determined technical parameters reveals a very good accuracy that is better than 1% for the resonant frequency.