The use of Gauss-Laguerre vector beams in STED microscopy.

This paper examines the use of Gauss-Laguerre beams in STED microscopy. These types of beams are shown to have beneficial properties that can be utilised to generate stable, high quality STED beams resulting in an aberration-resilient generation volume. In this paper we obtain general expressions for Gauss-Laguerre beams being focused through a stratified medium and describe their optimization for STED microscopy purposes. Our results show that the circularly polarised, lowest order "dark" beam is the most beneficial for STED purposes.