| Autor: |
Wenzel MT; Institute of Applied Photophysics, Technische Universität Dresden, 01062 Dresden, Germany. marc.tobias.wenzel@iapp.de, Härtling T, Olk P, Kehr SC, Grafström S, Winnerl S, Helm M, Eng LM |
| Jazyk: |
angličtina |
| Zdroj: |
Optics express [Opt Express] 2008 Aug 04; Vol. 16 (16), pp. 12302-12. |
| DOI: |
10.1364/oe.16.012302 |
| Abstrakt: |
We report on the implementation of metal nanoparticles as probes for scattering and apertureless near-field optical investigations in the mid-infrared (mid-IR) spectral regime. At these wavelengths, an efficient electric-field confinement is necessary and achieved here through a gold metal nanoparticle of 80 nm in diameter (Au80-MNP) acting as the optical antenna. The Au80-MNP is attached to a standard AFM cantilever used as the spatial manipulator. When approached to a sample surface while being illuminated with an infrared beam, the Au80-MNP produces a considerably improved spatial confinement of the electric field compared to an ordinary scattering AFM tip. We demonstrate here the confinement normal to the sample surface by making use of a sample-induced phonon polariton resonance in a ferroelectric lithium niobate sample. Our experimental findings are in very good agreement with the quasistatic dipole model and show improved optical resolution via well-selected antenna particles. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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