Superdirectivity by virtue of coupling between meta-atoms

We explore the possibility of achieving superdirectivity in metamaterials by relying on magnetoinductive waves, short-wavelength slow waves capable of providing rapidly varying current distribution. Using a dimer of magnetically coupled split rings we identify conditions for achieving superdirectivity in terms of the dimer size, the coupling strength and the quality factor. Predictions of the analytical model are verified numerically. Our results might lead to the first realization of genuine superdirective antenna arrays.