Berlin 2012 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 74: Plasmonics and nanooptics IV
O 74.10: Vortrag
Donnerstag, 29. März 2012, 18:15–18:30, MA 005
Excitation of radial and other complex polarization states in special optical fibers by long period fiber gratings — •Christoph Zeh1, Rico Illing1, Bernd Köhler1, Jörg Opitz1, and Lukas M. Eng2 — 1Fraunhofer Institut für Zerstörungsfreie Prüfverfahren, Institutsteil Dresden, Maria-Reiche-Str. 2, 01109 Dresden — 2Institut für Angewandte Photophysik, TU Dresden, 01069 Dresen
Radial polarization has drawn much attention in recent years, especially in the nano-optics and plasmonics community, because of its enhanced focusing properties as well as its ability to efficiently excite plasmons in radially symmetric structures.
Here, we present polarization mode excitation by long period fiber gratings (LPGs) in a special optical fiber. LPGs are able to efficiently transfer energy between co-propagating modes of the fiber. Since the field of a waveguide can always be represented as a set of mode fields with respective amplitudes and phases, polarization control is achieved by controlling the relative amplitudes and phases of the guided modes. We will demonstrate the use of a tunable acoustic LPG for this task and compare the results to other mechanical and UV-induced gratings.
The special fiber used in the above experiments is simulated by the multiple multipole technique (MMP) for a better understanding of the mode fields. This results in the transverse vector fields and propagation constants of the modes. The latter are necessary for designing the LPGs and for understanding the measurement results.