Polarization Generation and Manipulation Based on Nonlinear Plasmonic Metasurfaces

Abstract Polarization is one of the most important properties of light, which is also a typical dimension for light field manipulation. With specially designed meta‐atoms and tailorable phase distribution, metasurfaces have been employed to achieve arbitrary polarization state in linear regime. Moreover, metasurface is also a platform for various types of nonlinear light generation, which can be used to realize an integrated polarized light source combined with its powerful capability of polarization manipulation. Here, a nonlinear plasmonic metasurface that is able to simultaneously realize nonlinear light generation and polarization manipulation is demonstrated. Two separated second harmonic (SH) beams with orthogonal circular polarizations are achieved from a linearly polarized fundamental wave (FW), and illuminated by circularly polarized FW the same nonlinear plasmonic metasurface can generate linearly polarized SH, which can be viewed as an SH quarter‐wave plate. Furthermore, arbitrary elliptical polarized SH can also be obtained from properly designed nonlinear metasurfaces. This design provides a new approach for miniaturized light source for special polarization requirement, which may have potential applications in integrated optics.