Surface Plasmon Resonance sensor showing enhanced sensitivity for CO2 detection in the mid-infrared range.
We present the first optical sensor based on Surface Plasmon Resonance (SPR) operating in the mid-infrared range. The experimental setup is based on a Kretschmann geometry with Ti/Au layers deposited on a CaF(2) prism where light excitation is provided by a Quantum Cascade Laser (QCL) source. Evidence of SPR is presented and the sensing capability of the system is demonstrated by using CO(2) and N(2) mixtures as test samples. Due to the absorption of CO(2) at this wavelength, it is shown that the sensitivity of this configuration is five times higher than a similar SPR sensor operating in the visible range of the spectrum.
Herminjard
Sylvain
S
Institute of Microtechnology, University of Neuchâtel, CH-2000 Neuchâtel, Switzerland. sylvain.herminjard@unine.ch
Sirigu
Lorenzo
L
Herzig
Hans Peter
HP
Studemann
Eric
E
Crottini
Andrea
A
Pellaux
Jean-Paul
JP
Gresch
Tobias
T
Fischer
Milan
M
Faist
Jérôme
J
D000042:Absorption; D002124:Calcium Fluoride / Q000737:chemistry; D002245:Carbon Dioxide / Q000032:analysis*; D006046:Gold; D007259:Infrared Rays; D009584:Nitrogen; D012031:Refractometry; D012680:Sensitivity and Specificity; D013055:Spectrophotometry, Infrared; D020349:Surface Plasmon Resonance; D014025:Titanium
D002245:Carbon Dioxide; D006046:Gold; D014025:Titanium; D009584:Nitrogen; D002124:Calcium Fluoride