A novel set of boundary conditions requiring vanishing of the normal components of the D and B vectors at the boundary surface was introduced recently and labeled as the DB-boundary conditions. Basic properties of a resonator structure defined by the spherical DB boundary are studied in this paper. It is shown that the resonance modes polarized TE and TM with respect to the radial direction coincide with those of the respective PEC and PMC resonators. Modes in the DB resonator show higher degree of degeneracy than those of the PEC resonator which may find application in materials research.
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