SKM 2023 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

O: Fachverband Oberflächenphysik

O 91: Plasmonics and Nanooptics V: Waveguides and Antennas

O 91.7: Talk

Friday, March 31, 2023, 12:00–12:15, CHE 89

Laser Printing of Plasmonic Dimers on Optical Fiber Tips for Fiber-based SERS — •Paul Vosshage, Francis Schuknecht, and Theobald Lohmüller — Chair for Photonics and Optoelectronics, Nano-Institute Munich, Department of Physics, Ludwig-Maximilians-Universität, Königinstraße 10, 80539 Munich, Germany

Raman Spectroscopy through optical fibers offers great flexibility for conducting measurements both in situ and in vivo, but shows limitations due to the weak Raman scattering cross-sections of most molecules and a considerable background introduced by the fiber material itself. However, a strong signal amplification can be obtained via surface enhanced Raman scattering (SERS) by introducing plasmonic hot-spots on the optical fiber tip.
Here, we demonstrate a single-step approach to pattern plasmonic dimer antennas directly onto glass fibers by optical means. A focused laser beam is used to transform a gold nanorod into two nanospheres of equal size via heating. Simultaneously, optical forces are harnessed to print the two spheres onto the fiber tip as a strongly coupled dimer. The resulting plasmonic dimers feature nm-sized gaps, which provide a strong electromagnetic field enhancement required for fiber-based SERS.