Geometric spin Hall effect of light in tightly focused polarization tailored light beams

TL;DR

This paper experimentally demonstrates the geometric spin Hall effect of light in tightly focused vector beams, revealing polarization-dependent intensity shifts linked to transverse angular momentum in a purely geometric context.

Contribution

It provides the first experimental verification of the geometric spin Hall effect of light in tightly focused beams using nano-probing and reconstruction techniques.

Findings

Verified polarization-dependent intensity shifts in focused beams

Linked shifts to transverse angular momentum

Confirmed geometric origin of the effect

Abstract

Recently, it was shown that a non-zero transverse angular momentum manifests itself in a polarization dependent intensity shift of the barycenter of a paraxial light beam [A. Aiello et al., Phys. Rev. Lett. 103, 100401 (2009)]. The underlying effect is phenomenologically similar to the spin Hall effect of light, but does not depend on the specific light-matter interaction and can be interpreted as a purely geometric effect. Thus, it was named the geometric spin Hall effect of light. Here, we experimentally investigate the appearance of this effect in tightly focused vector-beams. We use an experimental nano-probing technique in combination with a reconstruction algorithm to verify the relative shifts of the components of the electric energy density in the focal plane, which are linked to the intensity shift. By that, we experimentally demonstrate the geometric spin Hall effect of light in a focused light beam.