Open AccessAll-semiconductor plasmonic gratings for biosensing applications in the mid-infrared spectral range
Author(s) -
Franziska Barho,
Ф. Гонзалез-Посада,
Maria-José Milla-Rodrigo,
M. Bomers,
L. Cerutti,
Thierry Taliercio
Publication year - 2016
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.016175
Subject(s) - materials science , grating , plasmon , optics , surface plasmon resonance , refractive index , infrared , optoelectronics , surface plasmon , biosensor , absorption (acoustics) , nanotechnology , physics , nanoparticle , composite material
We propose 1D periodic, highly doped InAsSb gratings on GaSb substrates as biosensing platforms applicable for surface plasmon resonance and surface enhanced infrared absorption spectroscopies. Based on finite-difference time-domain simulations, the electric field enhancement and the sensitivity on refractive index variations are investigated for different grating geometries. The proposed, optimized system achieves sensitivities of 900 nm RIU -1 . A clear red shift of the plasmon resonance as well as the enhancement of an absorption line are presented for 2 nm thin adlayers in simulations. We experimentally confirm the high sensitivity of the InAsSb grating by measurements of the wavelength shift induced by a 200 nm thin polymethylmethacrylate layer and demonstrate an enhancement of vibrational signals. A comparison to a gold grating with equivalent optical properties in the mid-infrared is performed. Our simulations and experimental results underline the interest in the alternative plasmonic material InAsSb for highly sensitive biosensors for the mid-infrared spectral range.