Single-Layer Bifacial Metasurface: Full-Space Visible Light Control

Optical metasurfaces have attracted considerable attention thanks to their unprecedented ability to control the electromagnetic properties of light in subwavelength scale. These metasurface-integrated devices not only have the merit of compact form factor but also exhibit some better performance in comparison with conventional bulk optic devices. In this work, a novel metasurface that enables full-space light control is realized, offering an unconventional functionality that provides a new foothold for metasurface integration in optics. Multipolar interference and Pancharatnam-Berry phase are combined with each other and suggested as a physical background for the proposed device. As an example of the functionality, asymmetric beam steering and hologram generation are proposed and measured experimentally. As far as it is known, this is the first work achieving full-space control in visible range. Thanks to its manufactural ease and unprecedented function capability, this work will offer innovative potentials to be utilized in various integrated optic devices that need miniaturization or implementation of ingenious and light-weight optical components used in optical systems for photography, microscopy, computer vision, etc.