Regensburg 2016 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 23: Plasmonics and Nanooptics: Light-Matter Interaction, Spectroscopy
O 23.4: Poster
Montag, 7. März 2016, 18:15–20:30, Poster E
Incident Angle-Tuning of Infrared Antenna Array Resonances for Molecular Sensing — •Andreas Hessler, Tobias W.W. Mass, and Thomas Taubner — Institute of Physics (IA) RWTH Aachen
Metallic structures can efficiently couple light into a region of subwavelength size. In these regions, large local field enhancements can occur and enable an increased absorption of molecules which are placed in these so called "hot spots". Arrays of metallic structures which are designed for surface enhanced infrared absorption spectroscopy (SEIRA) enable the detection of molecular vibrations with high sensitivity [1,2].
In recent work [3], we apply incident angle-tuning to antenna array resonances in order to optimize the enhancement of two adjacent vibrational bands of a self-assembled thiol-monolayer. Varying the incident angle shifts the spectral positions at which collective excitation and peak field enhancement of the antennas occur. This allows a spectral tuning of the array resonance without changing geometry or surrounding material of the antennas.
Additionally, we now investigate the enhancement of vibrational modes of different numbers of CH2-bonds by varying the chain lengths of the surface molecules.
[1] R.Adato et al., P. Natl. Acad. Sci. USA, 106, 19227, 2009
[2] F.Neubrech et al., Phys. Rev. Lett, 101, 157403, 2008
[3] T.W.W.Maß and T.Taubner, ACS Photonics, 2, 1498, 2015