  We report the design, fabrication, and characterization of bianisotropic
Huygens' metasurfaces (BHMSs) for refraction of normally incident beams towards
71.8 degrees. As previously shown, all three BHMS degrees of freedom, namely,
electric polarizability, magnetic polarizability and omega-type magnetoelectric
coupling, are required to ensure no reflections occur for such wide-angle
impedance mismatch. The unit cells are composed of three metallic layers,
yielding a printed-circuit-board (PCB) structure. The fabricated BHMS is
characterized in a quasi-optical setup, used to accurately assess specular
reflections. Subsequently, the horn-illuminated BHMS' radiation pattern is
measured in a far-field chamber, to evaluate the device's refraction
characteristics. The measured results verify that the BHMS has negligible
reflections, and the majority of the scattered power is coupled to the
desirable Floquet-Bloch mode. To the best of our knowledge, this is the first
experimental demonstration of such a reflectionless wide-angle refracting
metasurface.
