In linear optical regime, it is shown that the polarization, amplitude, and phase of light can be easily controlled by using optical metasurfaces, thus enabling the powerful designs of metalenses, high‐efficiency holograms, and so on. In comparison, the manipulation of nonlinear optical processes on the metasurfaces is much more challenging. This is mainly because the metasurface nonlinear source is also modulating the waves emitted from it. Thus, designing nonlinear meta‐atoms with multiple optical functionalities is highly desirable. Herein, the broadband and near‐unity nonlinear optical circular dichroism (CD) of second harmonic generation from a nano‐kirigami plasmonic metasurface is experimentally demonstrated, which is free‐standing with total thickness of about one‐third of the excitation wavelength. The broadband and near unity nonlinear CD is attributed to both the strong CD of fundamental wavelengths and spin‐controlled second harmonic generations from the nano‐kirigami meta‐atoms with threefold rotational symmetries. The proposed nonlinear nano‐kirigami metasurface provides a novel platform for realizing various nonlinear optical functionalities at the nanoscale.

中文翻译：

---

具有巨大非线性光学圆二色性的纳米千纸超表面

在线性光学系统中，表明可以通过使用光学超表面轻松控制光的偏振，幅度和相位，从而实现强大的Metalenses，高效全息图等设计。相比之下，在超颖表面上进行非线性光学过程的操作更具挑战性。这主要是因为超表面非线性源也在调制从其发出的波。因此，非常需要设计具有多种光学功能的非线性亚原子。在此，实验证明了从纳米千里拉等离子体等离子体超表面产生二次谐波的宽带和近统一的非线性光学圆二色性（CD），它是独立的，其总厚度约为激发波长的三分之一。宽带和接近统一的非线性CD既归因于基本波长的强CD，也归因于具有三重旋转对称性的纳米krigami原子的自旋控制二次谐波生成。提出的非线性纳米千纸鹤超颖表面为实现纳米尺度上的各种非线性光学功能提供了一个新颖的平台。