Abstract:The primary objective of this study is the development of transparent thin film materials in the IR enabling strong infrared absorption of organic compounds in the vicinity of metal nanoparticles by the surface plasmon effect. For developing these optical micro-sensors, heterostructures combining gold nanoparticles and chalcogenide planar waveguides are fabricated and adequately characterized. Single As 2 S 3 and Ge 25 Sb 10 Se 65 amorphous chalcogenide thin films are prepared by radiofrequency magnetron sputtering. For the fabrication of gold nanoparticles on a chalcogenide planar waveguide, direct current sputtering is employed. Fabricated single layers or hetero-structures are characterized using various techniques to investigate the influence of deposition parameters. The nanoparticles of gold are functionalized by a self-assembled monolayer of 4-nitrothiophenol. Finally, the surface enhanced infrared absorption spectra of 4-nitrothiophenol self-assembled on fabricated Au/Ge-Sb-Se thin films hetero-structures are measured and analyzed. This optical component presents a ~24 enhancement factor for the detection of NO 2 symmetric stretching vibration band of 4-nitrothiophenol at 1336 cm −1 . 232-239 (1999). 19. L. Tichý, H. Ticha, P. Nagels, R. Callaerts, R. Mertens, and M. Vlcek, "Optical properties of amorphous As-Se and Ge-As-Se thin films," Mater. Lett. 39(2), 122-128 (1999). 20. J. Charrier, M. L. Anne, H. Lhermite, V. Nazabal, J. P. Guin, F. Charpentier, T. Jouan, F. Henrio, D. Bosc, and J. L. Adam, "Sulphide GaxGe25-xSb10S65(x=0,5) sputtered films: Fabrication and optical characterizations of planar and rib optical waveguides," J. Appl.

No abstract

International audienceThe development of infrared sensing platform requires adapted materials. In this work, we used sputtered gold nanoparticles on a chalcogenide glass to demonstrate that these infrared materials can be used as substrate for surface enhanced infrared absorption (SEIRA) spectroscopy. The sputtering parameters were optimized to get the highest possible enhancement. To assess it, a self-assembled monolayer of 4-nitrothiophenol was used. These preliminary results are promising and pave the way for various configurations of waveguide for integrated optical components