Reversible Wavefront Shaping Between Gaussian and Airy Beams By Mimicking Gravitational Field

TL;DR

This study demonstrates a novel reversible wavefront shaping technique that transforms Gaussian beams into Airy-like accelerating beams and back, by mimicking gravitational fields in a specially designed micro-structured waveguide.

Contribution

We introduce the first reversible wavefront shaping method using a gravitational field analogy in a gradient-index waveguide, enabling bidirectional beam transformation.

Findings

Experimental validation of wavefront shaping between Gaussian and Airy beams.

Full-wave simulations confirm the experimental results.

Theoretical model explains beam evolution based on Landau's method.

Abstract

In this paper, we experimentally demonstrate reversible wavefront shaping through mimicking gravitational field. A gradient-index micro-structured optical waveguide with special refractive index profile was constructed whose effective index satisfying a gravitational field profile. Inside the waveguide, an incident broad Gaussian beam is firstly transformed into an accelerating beam, and the generated accelerating beam is gradually changed back to a Gaussian beam afterwards. To validate our experiment, we performed full-wave continuum simulations that agree with the experimental results. Furthermore, a theoretical model was established to describe the evolution of the laser beam based on Landau's method, showing that the accelerating beam behaves like the Airy beam in the small range in which the linear potential approaches zero. To our knowledge, such a reversible wavefront shaping technique has not been reported before.