Vector Beam Bending

TL;DR

This paper demonstrates that specially prepared vector beams with higher-order polarization gradients can follow curved trajectories in free space, revealing a new optical beam bending phenomenon independent of medium inhomogeneity or spacetime curvature.

Contribution

It introduces the concept that vector beams with second-order polarization gradients can bend in free space, supported by experimental validation.

Findings

Vector beams with second-order polarization gradients follow curved paths.

Experimental confirmation of beam bending in free space.

Theoretical framework based on optical intensity transport.

Abstract

It is well known that the trajectory of a light beam can curve if the medium in which the beam propagates is inhomogeneous or if the local spacetime is curved. In this paper we present a third possibility and show that a properly-prepared optical beam follows a curved trajectory even in free space where the spacetime is locally flat. By casting the problem in terms of transport of optical intensity, we show that a beam comprising a gradient in state of polarization to second order or higher (i.e., a specifically prepared vector beam) must also follow a curved trajectory. The effect is confirmed experimentally for the case of a second-order gradient in a linearly polarized vector beam.