| Autor: |
Martin Esmann, Simon F. Becker, Bernard B. da Cunha, Jens H. Brauer, Ralf Vogelgesang, Petra Groß, Christoph Lienau |
| Jazyk: |
angličtina |
| Rok vydání: |
2013 |
| Předmět: |
|
| Zdroj: |
Beilstein Journal of Nanotechnology, Vol 4, Iss 1, Pp 603-610 (2013) |
| Druh dokumentu: |
article |
| ISSN: |
2190-4286 |
| DOI: |
10.3762/bjnano.4.67 |
| Popis: |
We investigate the radiation patterns of sharp conical gold tapers, which were designed as adiabatic nanofocusing probes for scanning near-field optical microscopy (SNOM). Field calculations show that only the lowest order eigenmode of such a taper can reach the very apex and thus induce the generation of strongly enhanced near-field signals. Higher-order modes are coupled into the far field at finite distances from the apex. Here, we demonstrate experimentally how to distinguish and separate between the lowest and higher-order eigenmodes of such a metallic taper by filtering in the spatial frequency domain. Our approach has the potential to considerably improve the signal-to-background ratio in spectroscopic experiments at the nanoscale. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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