The parallel-plate resonator: An RF probe for MR and MRI studies over a wide frequency range

We explore the use of the parallel-plate resonator for the study of thin cuboid samples over a wide range of magnetic resonance frequencies. The parallel-plate resonator functions at frequencies from tens to hundreds of MHz. Seven parallel-plate resonators are presented and discussed in a frequency range from 8 to 500 MHz. Magnetic resonance experiments were performed on both horizontal and vertical bore magnet systems with lithium and hydrogen nuclei. Parallel-plate radiofrequency (RF) probes are easy to build and easy to optimize. Experiments and simulations showed good sensitivity of the parallel-plate RF probe geometry with a small decrease in sensitivity at higher frequencies.