Poincare Beams in Tight Focus

Abstract

The family of Poincare beams has three characteristics including two real-valued angular characteristics, which descibe a concrete polarisation state on the Poincare sphere and a third integer characteristic l determining the beam singularity order. It was theoretically and numerically shown that at l = 2, an energy backflow is generated near the optical axis. It was revealed that at certain Poincare beams characteristics, the energy flow revolves around the optical axis because of spin-orbital conversion. It was also demonstrated that a radial optical Hall phenomenon took place in the compact focus of Poincare beams.