Efficient Frequency Conversion with Geometric Phase Control in Optical Metasurfaces
| Title: | Efficient Frequency Conversion with Geometric Phase Control in Optical Metasurfaces |
|---|---|
| Authors: | Bernhard Reineke Matsudo, Basudeb Sain, Luca Carletti, Xue Zhang, Wenlong Gao, Costantino deAngelis, Lingling Huang, Thomas Zentgraf |
| Source: | Advanced Science, Vol 9, Iss 12, Pp n/a-n/a (2022) |
| Publisher Information: | Wiley, 2022. |
| Publication Year: | 2022 |
| Collection: | LCC:Science |
| Subject Terms: | bound states in the continuum, harmonic generation, metasurfaces, nonlinear optics, nonlinear vortex beams, Pancharatnam–Berry phase, Science |
| More Details: | Abstract Metasurfaces have appeared as a versatile platform for miniaturized functional nonlinear optics due to their design freedom in tailoring wavefronts. The key factor that limits its application in functional devices is the low conversion efficiency. Recently, dielectric metasurfaces governed by either high‐quality factor modes (quasi‐bound states in the continuum) or Mie modes, enabling strong light–matter interaction, have become a prolific route to achieve high nonlinear efficiency. Here, an effective way of spatial nonlinear phase control by using the Pancharatnam–Berry phase principle with a high third harmonic conversion efficiency of 10−4 W−2 is demonstrated both numerically and experimentally. It is found that the magnetic Mie resonance appears to be the main contributor to the third harmonic response, while the contribution from the quasi‐bound states in the continuum is negligible. This is confirmed by a phenomenological model based on coupled anharmonic oscillators. Besides, the metasurface provides experimentally a high diffraction efficiency (80%–90%) in both polarization channels. A functional application of this approach is shown by experimentally reconstructing an encoded polarization‐multiplexed vortex beam array with different topological charges at the third harmonic frequency with high fidelity. The approach has the potential viability for future on‐chip nonlinear signal processing and wavefront control. |
| Document Type: | article |
| File Description: | electronic resource |
| Language: | English |
| ISSN: | 2198-3844 20210450 |
| Relation: | https://doaj.org/toc/2198-3844 |
| DOI: | 10.1002/advs.202104508 |
| Access URL: | https://doaj.org/article/4b92985fda644d04b4f130b6f83dc955 |
| Accession Number: | edsdoj.4b92985fda644d04b4f130b6f83dc955 |
| Database: | Directory of Open Access Journals |
| ISSN: | 21983844 20210450 |
|---|---|
| DOI: | 10.1002/advs.202104508 |
| Published in: | Advanced Science |
| Language: | English |