Dresden 2014 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

O: Fachverband Oberflächenphysik

O 37: Posters: Plasmonics, Electronic Structure and Spin-Orbit Interaction, Semiconductor and Insulator Surfaces, Nanostructures

O 37.29: Poster

Dienstag, 1. April 2014, 18:30–22:00, P2

Active stabilization of a vector field synthesizer applied for spatiotemporal optical near-field control — •Stanislaw Nickel, Michael Birlo, Dominik Differt, and Walter Pfeiffer — Department of Physics, University Bielefeld, 33615 Bielefeld, Germany

Ultrafast spatiotemporal optical near-field control in nanostructures and random scattering media requires full control of spectral amplitude and phase for both polarizations components. Conventional polarization pulse shapers that rely on a common optical path for both polarization components are limited and thus also allow only limited optical near-field control. Vector field synthesizers use independent pathways and thus are no longer restricted in their pulse shaping capabilities. However, because of the independent pathways interferometric stability of the whole setup is required. Here we demonstrate stable and reliable generation of polarization shaped pulses using a vector field synthesizer with active stabilization mechanism to correct the inherent mechanical instabilities of the setup because of vibrations and thermal drift. The phase between both pathways in the setup is detected by adding light from a cw laser diode operating at a wavelength just outside the fs-laser spectrum and measuring the output polarization. Using a piezo-driven wedge (pair) and an analog PID controller, the relative phase between both pathways is stabilized. With active stabilization the standard deviation is smaller than 2π/50, i.e. 10 times improved compared to unstabilized operation, and no drift occurs over one hour.