Dresden 2011 – wissenschaftliches Programm
O 18.3: Vortrag
Montag, 14. März 2011, 17:45–18:00, PHY C213
Plasmonic nanostructures for strong light confinement fabricated using soft-lithography and plasma etching techniques — •Manuel Gonçalves1, Tobias Paust1, Fabian Enderle2, Stefan Wiedemann2, Alfred Plettl2, Paul Ziemann2, and Othmar Marti1 — 1Ulm University - Inst. of Experimental Physics, Albert-Einstein-Allee 11, 89069 Ulm, Germany — 2Ulm University - Inst. of Solid State Physics, Albert-Einstein-Allee 11, 89069 Ulm, Germany
Nanosphere lithography has been commonly used for fabrication of plasmonic nanostructures. Small triangular particles of less than 100 nm size, with sharp corners, can be obtained at low cost. These structures have been used for plasmonic based sensing applications.
We show how nanosphere lithography can be extended for fabrication of more complex structures as arrays of holes on corrugated dielectrica and arrays of metal-dielectric pillars, using in combination soft-lithography and reactive ion-etching techniques (ICP-RIE). Surface plasmon modes can be easily excited on metal coated periodic dielectric structures using light. On the other hand, geometrical singularities lead to strong localized surface plasmons. The fabricated structures can be used for plasmonic effects as enhanced optical transmission, light confinement and surface enhanced Raman spectroscopy, due to their geometrical and optical properties. Confocal microscopy and angle-resolved spectroscopy were used for study of far-field transmittance and reflectance. The near-fields were investigated by SNOM and confocal Raman microscopy. Simulations were carried out to obtain the near-fields and optical resonances.