Visualization and characterization of pure and coupled modes in water-based dielectric resonators on a human 7T...

MRI represents a unique method to visualize directly different resonant modes of arbitrarily-shaped dielectric resonators in the radiofrequency spectrum via construction of resonators filled with distilled, deionized water which has a low conductivity and high relative permittivity. The required dimensions, particularly for higher order modes, are large and so a high field whole-body MRI system is needed to visualize these modes. In this study, using a simple cylindrical geometry, many higher order modes were identified and confirmed using electromagnetic simulations. In addition, coupled modes between more than one resonator were investigated, with possible future applications including direct visualization of fields in metamaterials.