Schlickriede, ChristianKruk, SergeyWang, LeiSain, BasudebKivshar, YuriZentgraf, Thomas2022-07-132022-07-131530-6984http://hdl.handle.net/1885/268829Nonlinear metasurfaces incorporate many of the functionalities of their linear counterparts such as wavefront shaping, but simultaneously they perform nonlinear optical transformations. This dual functionality leads to a rather unintuitive physical behavior which is still widely unexplored for many photonic applications. The nonlinear processes render some basic principles governing the functionality of linear metasurfaces. Exemplarily, the superposition principle and the geometric optics approximation become not directly applicable to nonlinear metasurfaces. On the other hand, nonlinear metasurfaces facilitate new phenomena that are not possible in the linear regime. Here, we study the imaging of objects through a dielectric nonlinear metalens. We illuminate objects by infrared light and record their generated images at the visible third-harmonic wavelengths. We revisit the classical lens theory and suggest a generalized Gaussian lens equation for nonlinear imaging, verified both experimentally and analytically. We also demonstrate experimentally higher-order spatial correlations facilitated by the nonlinear metalens, resulting in additional image features.This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No 724306) and the the Deutsche Forschungsgemeinschaft (DFG) − SFB Geschäftszeichen TRR142/2-2020 − Projektnummer 231447078. S.K. thanks the Alexander von Humboldt Foundation for financial support.application/pdfen-AU© 2020 The authorshttp://creativecommons.org/licenses/ by-nc-nd/4.0/Metalensdielectric metasurfacenonlinear imagingthird-harmonic generationnonlinear Huygens’ principleNonlinear Imaging with All-Dielectric Metasurfaces202010.1021/acs.nanolett.0c011052021-08-01Creative Commons