Anomalous reflection from hybrid metamaterial slab.

We report for the first time that an ultra-thin hybrid metamaterial slab can reflect an incident plane wave in -1st diffraction order, giving rise to anomalous reflection in a "negative" way. The functionality is derived from the hybridized surface resonant states of the slab. The retro-directive reflection is demonstrated numerically for a Gaussian beam at oblique incidence and verified experimentally at microwave frequencies.