The key role of off-axis singularities in free-space vortex transmutation

TL;DR

This paper experimentally demonstrates how breaking rotational symmetry in free space can generate off-axis phase singularities during vortex transmutation, enabling advanced control of singularities for applications like atom trapping.

Contribution

It reveals the role of off-axis singularities in vortex transmutation caused by symmetry breaking, a novel insight into phase singularity dynamics.

Findings

Off-axis singularities follow straight dark rays bifurcating from the symmetry axis.

Symmetry breaking induces off-axis phase singularities in vortex transmutation.

Potential applications in atom trapping and particle manipulation.

Abstract

We experimentally demonstrate the generation of off-axis phase singularities in a vortex transmutation process induced by the breaking of rotational symmetry. The process takes place in free space by launching a highly-charged vortex, owning full rotational symmetry, into a linear thin diffractive element presenting discrete rotational symmetry. It is shown that off-axis phase singularities follow straight dark rays bifurcating from the symmetry axis. This phenomenon may provide new routes towards the spatial control of multiple phase singularities for applications in atom trapping and particle manipulation.