Abstract
Resonator made of two parallel PEMC (perfect electromagnetic conductor) planes with opposite PEMC admittance is studied. Except for degenerate cases, emerging at special PEMC admittance values, the modal fields are circularly polarized and they can be divided in four classes in terms of their polarization handedness and field symmetry. Resonance wavenumbers and Q values are derived for the resonance modes in the case of low losses. A degenerate resonance mode with non-circular polarization is studied as an example.