Researchers in the UK, Germany, Thailand and Hong Kong say they have made nonlinear metasurfaces in which they can continuously control the phase of the material’s nonlinear polarization for the first time. Compared with conventional techniques to do this, such as “poling”, the new approach allows for complete manipulation of the nonlinear signal’s wavefront and can remove unwanted nonlinear signals coming from so-called higher harmonic components, which can appear in poled materials. The new metasurfaces could be important for making nonlinear holograms, and nonlinear photonic crystals and circuits……
http://nanotechweb.org/cws/article/tech/60949
