Femto-Laser Processed Metasurface With Fano Response:Applications to a High Performance Refractometric Sensor  

作　　者：Mahmoud H.Elshorbagy Alejandro San-Blas Luis Miguel Sanchez-Brea Santiago M.Olaizola Jesús del Hoyo Angela Soria-Garcia Joaquin Andres-Porras Verónica Pastor-Villarrubia Javier Alda 

机构地区：[1]Physics Department,Faculty of Science,Minia University,El Minia 61519,Egypt [2]Applied Optics Complutense Group,Faculty of Optics and Optometry,Universidad Complutense de Madrid,Madrid28037,Spain [3]Ceit-Basque Research and Technology Alliance,Donostia-San Sebastian 20018,Spain [4]Electrical and Electronic Engineering Department,Universidad de Navarra,Donostia-San Sebastian 20018,Spain [5]Applied Optics Complutense Group,Optics Department,Faculty of Physics,Universidad Complutense de Madrid,Madrid 28040,Spain

出　　处：《Photonic Sensors》2025年第2期149-161,共13页光子传感器(英文版)

摘　　要：The practical development of compact modern nanophotonic devices relies on the availability of fast and low-cost fabrication techniques applicable to a wide variety of materials and designs.We have engraved a split grating geometry on stainless steel using femtosecond laser processing.This structure serves as a template to fabricate efficient plasmonic sensors,where a thick gold layer is grown conformally on it.The scanning electron microscope(SEM)images confirm the generation of the split laser-induced periodic spatial structures.The optical reflectance of our sensors shows two dips corresponding to the excitation of surface plasmon resonances(SPRs)at two different wavelengths.Furthermore,the asymmetric shape of these spectral responses reveals a strong and narrow Fano resonance.Our computational electromagnetism models accurately reproduce the reflectivity of the fabricated structure.The spectral responses of both the simulated and fabricated structures are fitted to the Fano model that coherently combines the narrow SPRs with the broad continuum background caused by diffraction.The parameters extracted from the fitting,such as the resonance wavelengths and line widths,are used to evaluate the performance of our device as a refractometric sensor for liquids.The maximum sensitivity and figure of merit are 880 nm/RIU and 80 RIU-1,respectively.Besides the compact design of our sensing device,its performance exceeds the theoretical maximum sensitivity of a classical Kretschmann setup.

关 键 词：PLASMONICS refractometric sensing Fano resonances laser-induced periodic surface structures 

分 类 号：O436[机械工程—光学工程]