Gold Nanocylinders on Gold Film as a Multi-spectral SERS Substrate

Wafa Safar (1) , Médéric Lequeux (2) , Jeanne Solard (3) , Alexis P. A. Fischer (3) , Nordin Félidj (4) , Pietro Giuseppe Gucciardi (5) , Mathieu Edely (1) , Marc Lamy De la Chapelle (1, 6)

1 IMMM - Institut des Molécules et Matériaux du Mans
2 CSPBAT - Chimie, Structures et Propriétés de Biomatériaux et d'Agents Thérapeutiques
3 LPL - Laboratoire de Physique des Lasers
4 ITODYS (UMR_7086) - Interfaces, Traitements, Organisation et Dynamique des Systèmes
5 IPCF - CNR Istituto per i Processi Chimico-Fisici
6 The Third Military Medical University

The surface enhanced Raman scattering (SERS) efficiency of gold nanocylinders deposited on gold thin film is studied. Exploiting the specific plasmonic properties of such substrates, we determine the influence of the nanocylinder diameter and the film thickness on the SERS signal at three different excitation wavelengths (532, 638 and 785 nm). We demonstrate that the highest signal is reached for the highest diameter of 250 nm due to coupling between the nanocylinders and for the lowest thickness (20 nm) as the excited plasmon is created at the interface between the gold and glass substrate. Moreover, even if we show that the highest SERS efficiency is obtained for an excitation wavelength of 638 nm, a large SERS signal can be obtained at all excitation wavelengths and on a wide spectral range. We demonstrate that it can be related with the nature of the plasmon (propagative plasmon excited through the nanocylinder grating) and with its angular dependence (tuning of the plasmon position with the excitation angle). Such an effect allows the excitation of plasmon on nearly the whole visible range, and paves the way to multispectral SERS substrates.

Mots clés: plasmon SERS optimization multi-spectral substrate; SERS; optimization; multi-spectral substrate

Domaines: Physique [physics]

Wafa Safar, Médéric Lequeux, Jeanne Solard, Alexis P. A. Fischer, Nordin Félidj, et al.. Gold Nanocylinders on Gold Film as a Multi-spectral SERS Substrate. Nanomaterials, 2020, The Biological Impact of Nanomaterials: From Safety Studies to Applications, 10 (5), pp.927. ⟨10.3390/nano10050927⟩. ⟨hal-04014576⟩