Inverse Engineered Micro‐Nano Polarized Photonics Device

ABSTRACT Polarization is one of the fundamental properties of light waves, and polarization manipulation plays a vital role in advanced optical applications. Micro‐nano optical devices have demonstrated powerful polarization manipulation capabilities, and their design approaches are no longer limited to forward design. With the rapid development of computer technology, inverse design has become an important supplement to traditional methods. Inverse‐designed micro‐nano polarization devices have realized polarization manipulation in various light propagation environments, including purely on‐chip, purely free‐space, and between the space and the chip. However, there is still a lack of systematic reviews on inverse‐designed micro‐nano polarization devices, which, to some extent, hinders the development of polarization device design technology. This paper focuses on the principles and technological development of inverse design for polarization devices in different propagation environments. A comprehensive review and discussion are conducted on the inverse design of micro‐nano polarization devices in purely free‐space, purely on‐chip, and space‐on‐chip environments. The advantages and disadvantages of various inverse design methods are compared and analyzed, along with their applicability to the design of polarization devices. This work aims to help researchers break through the cognitive barriers of inverse design across different propagation environments, thereby accelerating the progress of micro‐nano polarization device design.