High-angle deflection of metagrating-integrated laser emission for high-contrast microscopy.

Autor: Juodėnas M; Department of Physics, Chalmers University of Technology, 412 96, Gothenburg, Sweden. mindaugas.juodenas@chalmers.se., Strandberg E; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Grabowski A; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Gustavsson J; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Šípová-Jungová H; Department of Physics, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Larsson A; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Käll M; Department of Physics, Chalmers University of Technology, 412 96, Gothenburg, Sweden. mikael.kall@chalmers.se.
Jazyk: angličtina
Zdroj: Light, science & applications [Light Sci Appl] 2023 Oct 13; Vol. 12 (1), pp. 251. Date of Electronic Publication: 2023 Oct 13.
DOI: 10.1038/s41377-023-01286-0
Abstrakt: Flat metaoptics components are looking to replace classical optics elements and could lead to extremely compact biophotonics devices if integrated with on-chip light sources and detectors. However, using metasurfaces to shape light into wide angular range wavefronts with high efficiency, as is typically required in high-contrast microscopy applications, remains a challenge. Here we demonstrate curved GaAs metagratings integrated on vertical-cavity surface-emitting lasers (VCSELs) that enable on-chip illumination in total internal reflection and dark field microscopy. Based on an unconventional design that circumvents the aspect ratio dependent etching problems in monolithic integration, we demonstrate off-axis emission centred at 60° in air and 63° in glass with > 90% and > 70% relative deflection efficiency, respectively. The resulting laser beam is collimated out-of-plane but maintains Gaussian divergence in-plane, resulting in a long and narrow illumination area. We show that metagrating-integrated VCSELs of different kinds can be combined to enable rapid switching between dark-field and total internal reflection illumination. Our approach provides a versatile illumination solution for high-contrast imaging that is compatible with conventional microscopy setups and can be integrated with biophotonics devices, such as portable microscopy, NIR-II range bioimaging, and lab-on-a-chip devices.
(© 2023. Changchun Institute of Optics, Fine Mechanics and Physics (CIOMP), CAS.)
Databáze: MEDLINE