  The toroidal response is numerically investigated in a multifold double-ring
metamaterials at the antibonding magnetic-dipole mode (i.e., antiparallel
magnetic dipoles in one double-ring fold). This intriguing toroidal resonance
in metamaterials is considered as a result of the magnetoelectric effect due to
the broken balance of the electric near-field environment. We demonstrate that
the toroidal dipole response in metamaterials can improve the quality factor of
the resonance spectrum. In viewing of the design flexibility on the double-ring
geometry, such toroidal metamaterials will offer advantages in application
potentials of toroidal dipolar moment.
