All-dielectric metasurface beam deflector at the visible frequencies

Beam deflectors are important optical elements which can control the propagation direction of the beam in free space. However, with the development of miniaturization of the optical systems, conventional reflector-based mechanical beam deflectors confront a huge challenge due to their large sizes and incompatibility to the device integration. Here we propose an all-dielectric flat metasurface beam deflector which is composed of a single layer array of TiO₂ nanoantennas resting on a fused-silica substrate. Numerical simulations are performed to demonstrate that the proposed deflectors are able to efficiently deflect the incident beam for different angles with transmission efficiency higher than 80% at visible frequencies. This ultrathin all-dielectric metasurface deflector may have great potential applications in integrated optics.