Wave-Shaping Surfaces

Ultrathin screens made of metamaterials can bend or reshape a wave transmitted through them without generating any reflection.

Controlling light has fascinated mankind since the dawn of civilization, and the centuries of studies leading to the development of modern optics can still be a great source of inspiration. The advent of metamaterials—artificial materials with unconventional properties built by assembling smaller-than-wavelength constituent elements—has opened new venues for the manipulation of light propagation. Now, writing in Physical Review Letters, Carl Pfeiffer and Anthony Grbic from the University of Michigan, Ann Arbor, report the experimental demonstration, inspired by a three-century-old optical principle, of a new “metasurface”: a metamaterial-based thin screen capable of reshaping, in arbitrary ways, a radio-frequency wave transmitted through it, while at the same time minimizing undesired reflections [1].