All-dielectric metasurfaces for polarization manipulation: principles and emerging applications

Metasurfaces, composed of specifically designed subwavelength units in a two-dimensional plane, offer a new paradigm to design ultracompact optical elements that show great potentials for miniaturizing optical systems. In the past few decades, metasurfaces have drawn broad interests in multidisciplinary communities owing to their capability of manipulating various parameters of the light wave with plentiful functionalities. Among them, pixelated polarization manipulation in the subwavelength scale is a distinguished ability of metasurfaces compared to traditional optical components. However, the inherent ohmic loss of plasmonic-type metasurfaces severely hinders their broad applications due to the low efficiency. Therefore, metasurfaces composed of high-refractive-index all-dielectric antennas have been proposed to achieve high-efficiency devices. Moreover, anisotropic dielectric nanostructures have been shown to support large refractive index contrast between orthogonal polarizations of light and thus provide an ideal platform for polarization manipulation. Herein, we present a review of recent progress on all-dielectric metasurfaces for polarization manipulation, including principles and emerging applications. We believe that high efficient all-dielectric metasurfaces with the unprecedented capability of the polarization control can be widely applied in areas of polarization detection and imaging, data encryption, display, optical communication and quantum optics to realize ultracompact and miniaturized optical systems.