Enhanced biochemical sensing with high-Q transmission resonances in free-standing membrane metasurfaces

• DOI: 10.1364/optica.549393
• Publication Date: 2025-01-21T17:00:24Z
• Authors: Samir Rosas; Wihan Adi; Aidana Beisenova; Shovasis Kumar Bi...; Furkan Kuruoglu; Hongyan Mei; Mikhail A. Kats; David A. Czaplewski; Yuri S. Kivshar; Filiz Yesilkoy
• Keywords: FOS: Physical sciences; Physics - Applied Physics; Applied Physics (physics.app-ph); Physics - Optics; Optics (physics.optics)

Optical metasurfaces provide novel solutions to label-free biochemical sensing by localizing light resonantly beyond the diffraction limit, thereby selectively enhancing light-matter interactions for improved analytical performance. However, high-Q resonances in are usually achieved reflection mode, which impedes metasurface integration into compact imaging systems. Here, we demonstrate a platform advanced based on physics of bound states continuum (BIC) and electromagnetically induced transparency (EIT) modes, arise when two interfering from periodic pattern tilted elliptic holes overlap both spectrally spatially, creating narrow window mid-infrared spectrum. We experimentally measure these resonant peaks observed transmission mode (Q~734 @ λ~8.8 μm) free-standing silicon membranes confirm their tunability through geometric scaling. also strong coupling BIC-EIT modes with thinly coated PMMA film metasurface, characterized large Rabi splitting (32 cm-1) biosensing protein monolayers mode. Our new photonic can facilitate sensors monolithic optical systems while being compatible scalable manufacturing, clearing way on-site everyday applications.