Metasurface Holograms with Arbitrary Phase Control of Electromagnetic Wavefront

We propose and demonstrate a metasurface hologram for arbitrary image using an active metasurface structure with tunable phase-control unit cells. The phase information of the hologram image is calculated with an adaptive Gerchberg-Saxton algorithm, between the image plane and the diffraction plane, which can be achieved using active phase control metasurface. The phase control of unit cells can be realized by changing electric capacity in series with a pair of subwavelength metallic sticks.