The principle and research progress of metasurfaces

Metasurfaces, a specific type of subwavelength-scale two-dimensional(2D) array, have shown great flexibilities to control the light field. Metasurfaces possess the unique advantages of ultrathin, low-loss and easy fabrication, therefore attract immense attentions and show broad prospects for applications. This paper reviews recent progress in the physics of metasurfaces and the applications for generalized refraction and reflection, polarization conversion, controlling the orbit angular moment of light and computer generated holography(CGH). Due to the extra design freedom and powerful functionality, metasurfaces allow the possibility to substitute the conventional optical components in a variety of applications. In the future, novel types of metasurfaces with broadband, high efficiency, multi-task and active tunability are still highly desired and of great value.