Analysis of capacitive coupling and associated loss for a solenoidal magnetic resonance imaging radio-frequency coil

Presented is an analysis of the capacitive coupling between a magnetic resonance imaging radio-frequency (rf) coil and a dielectric sample. Calculated is the coil self-capacitance and power loss in the medium. The capacitively coupled power loss is compared with the more familiar inductively coupled eddy current loss and the predicted dependence of self-capacitance on coil and sample size is studied experimentally in a series of single-turn slotted solenoids of various sizes.