Controlling light with metamaterial-based nonlinear photonic crystals

Since the seminal paper by Bloembergen and colleagues on nonlinear optical interactions(1), this field has supplied some of the most important contributions to optics-related science and applications, including the exceptional ability to generate coherent light throughout the optical spectrum(2-4). Recently, a new family of nanostructured optical materials, so called metamaterials, with artificial effective nonlinearities has been demonstrated(5-10). Controlling their nonlinear output has the potential to open up a whole new area of fundamental research and lead to the development of efficient, active, integrated and ultra-compact nonlinear optical devices. Here, we experimentally demonstrate unprecedented control over the nonlinear emission from metamaterials by constructing the first nonlinear metamaterial-based photonic crystals. We specifically demonstrate engineered nonlinear diffraction and all-optical scanning, enabling ultra-wide angular scanning of the nonlinear output from the metamaterial. We also demonstrate intense focusing of the nonlinear signal directly from the metamaterial, resulting in an intensity enhanced by nearly two orders of magnitude.