Ultrathin 3R-MoS2 metasurfaces with atomically precise edges for efficient nonlinear nanophotonics
Journal article, 2025
Dielectric metasurfaces that combine high-index materials with optical nonlinearities are recognized for their potential in quantum and classical nanophotonic applications. However, the fabrication of high-quality metasurfaces poses material-dependent challenges, as their designs are often susceptible to disorder, defects, and scattering losses, mostly occurring at the edges of nanostructured features. Additionally, the choice of the material platforms featuring second-order optical nonlinearities χ(2), is limited to broken-inversion symmetry crystals such as GaAs, GaP, LiNbO3, and various bulk van der Waals materials. Here, we use a combination of top-down lithography and anisotropic wet etching of a specially stacked van der Waals crystal – 3R-MoS2, which exhibits both a high refractive index and exceptional χ(2) nonlinearity, to produce ultrathin (~20–25 nm) metasurfaces with atomically sharp edges, where the etching breaks the in-plane symmetry of the meta-atoms. The broken symmetry manifests as a quasi-boundstate-in-the-continuum, enabling the enhancement of second-harmonic generation of three orders of magnitude at specific wavelengths.
Author
Georgii Zograf
Chalmers, Physics, Nano and Biophysics
Betül Kücüköz
Chalmers, Physics, Nano and Biophysics
Aleksandr Poliakov
Chalmers, Physics, Nano and Biophysics
Andrew Yankovich
Chalmers, Physics, Nano and Biophysics
Alok Ranjan
Chalmers, Physics, Nano and Biophysics
Maria Bancerek
University of Warsaw
Abhay V. Agrawal
Chalmers, Physics, Nano and Biophysics
Eva Olsson
Chalmers, Physics, Nano and Biophysics
Witlef Wieczorek
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Technology
Tomasz Antosiewicz
Chalmers, Physics, Bionanophotonics
University of Warsaw
Timur Shegai
Chalmers, Physics, Nano and Biophysics
Communications Physics
23993650 (eISSN)
Vol. 8 1 271Plasmon-exciton coupling at the attosecond-subnanometer scale: Tailoring strong light-matter interactions at room temperature
Knut and Alice Wallenberg Foundation (2019.0140), 2020-07-01 -- 2025-06-30.
2D material-based technology for industrial applications (2D-TECH)
VINNOVA (2024-03852), 2023-11-01 -- 2029-12-31.
VINNOVA (2019-00068), 2020-05-01 -- 2024-12-31.
GKN Aerospace Sweden (2D-tech), 2021-01-01 -- 2024-12-31.
Tunable optical resonators and metamaterials through Casimir self-assembly
Swedish Research Council (VR) (2022-03347), 2023-01-01 -- 2026-12-31.
Subject Categories (SSIF 2025)
Atom and Molecular Physics and Optics
Condensed Matter Physics
Other Physics Topics
DOI
10.1038/s42005-025-02194-y