Subwavelength dielectric resonators assembled into metasurfaces have become a versatile tool for miniaturizing optical components approaching the nanoscale^1,2,3. An important class of metasurface functionalities is associated with asymmetry in both the generation and transmission of light with respect to reversals of the positions of emitters and receivers^4,5,6. The nonlinear light–matter interaction in metasurfaces^7,8,9 offers a promising pathway towards miniaturization of the asymmetric control of light. Here we demonstrate asymmetric parametric generation of light in nonlinear metasurfaces. We assemble dissimilar nonlinear dielectric resonators into translucent metasurfaces that produce images in the visible spectral range on being illuminated by infrared radiation. By design, the metasurfaces produce different and completely independent images for the reversed direction of illumination, that is, when the positions of the infrared emitter and the visible light receiver are exchanged. Nonlinearity-enabled asymmetric control of light by subwavelength resonators paves the way towards novel nanophotonic components via dense integration of large quantities of nonlinear resonators into compact metasurface designs.

组装成超表面的亚波长介电谐振器已成为一种多功能工具，用于使接近纳米级的光学元件小型化^1,2,3。一类重要的超表面功能与光的产生和传输中的不对称性有关，这与发射器和接收器^4,5,6的位置反转有关。超表面中的非线性光-物质相互作用^7,8,9为光的不对称控制的小型化提供了一条有希望的途径。在这里，我们展示了非线性超曲面中光的不对称参数生成。我们将不同的非线性介电谐振器组装成半透明的超表面，在红外辐射照射下产生可见光谱范围内的图像。通过设计，当红外发射器和可见光接收器的位置交换时，超表面会为相反的照明方向产生不同且完全独立的图像。亚波长谐振器对光的非线性非对称控制通过将大量非线性谐振器密集集成到紧凑的超表面设计中，为新型纳米光子元件铺平了道路。