Abstract：As a new concept originated in early 21st century, metamaterials have since attracted extensive attention of both scientific research and industry. Different from traditional materials, the properties of the metamaterials are created by artificial structures instead of intrinsic compositions of the materials, thus they exhibit many extrondinary properties beyond nature. Optical materials is one of the most important parts in this field, playing a significant role in information technology. In 2020, there were a lot of excellent research works in the optical metamaterials field. Here, we give a comprehensive review based on the works in nonlinear optical metamaterials, artificial intelligence metamaterials, and optical metasurface.
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2021, Vol. 39 
