Leiden University Student Repository

Stam, W.G. (2019)

Strongly focused vortices and pinhole scanning microscopy

Master thesis | Physics (MSc)

Over the last few decades, several methods have been explored and applied to circumvent the Abbe-Rayleigh diffraction limit, probably most importantly, stochastic super-resolution fluorescence microscopy methods. Another possibility, relying only on linear classical optics, is to exploit optical superoscillations, and is far less explored to date. In this project we explore the use of optical vortices for super-resolution far-field imaging. For this, we investigate strongly focused optical fields using a number of theoretical methods, we implement an experiment where a micro-pinhole is scanned through the focus, and, explore spin-orbit interactions of strongly focused optical fields. We find that our micron-sized pinhole is able to discern structures much smaller than its own size and leads to an enhancement of the spin-orbit interaction. Our method can be implemented as a simple and fast tool for characterizing the intensity distribution of a focused field with high resolution.

vortex beams

pinhole

tightly focused

strongly focused

superresolution

subdiffraction

spin-orbit coupling

optics

Author

Stam, W.G.

Faculty

Faculty of Science

Specialisation

QMO

Supervisors

Löffler, Wolfgang

ECTS Credits

4

Language

en