Details

Autor(en) / Beteiligte

• Juodėnas, Mindaugas
• Strandberg, Erik
• Grabowski, Alexander
• Gustavsson, Johan
• Šípová-Jungová, Hana
• Larsson, Anders
• Käll, Mikael

Titel

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

Ist Teil von

• Light, science & applications, 2023-10, Vol.12 (1), p.251-251, Article 251

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2023

Quelle

Elektronische Zeitschriftenbibliothek - Frei zugängliche E-Journals

Beschreibungen/Notizen

• 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. Integration of curved GaAs metagratings onto VCSELs enables a compact on-chip illumination solution for high-contrast microscopy, making it a versatile choice for light sources in lab-on-a-chip devices.