Continuous Variable Entanglement and Squeezing of Orbital Angular Momentum States

TL;DR

This paper presents the first experimental demonstration of continuous variable orbital angular momentum states, showcasing quadrature entanglement and squeezing in first-order Laguerre-Gauss modes using a non-degenerate optical parametric oscillator.

Contribution

It introduces the first experimental characterization of continuous variable OAM states and demonstrates squeezing and entanglement in these modes.

Findings

Quadrature entanglement between first-order Laguerre-Gauss modes.

Squeezing of orbital angular momentum parameters.

Reconstruction of the uncertainty volume on the orbital Poincare sphere.

Abstract

We report the first experimental characterization of the first-order continuous variable orbital angular momentum states. Using a spatially non-degenerate optical parametric oscillator (OPO) we produce quadrature entanglement between the two first-order Laguerre-Gauss modes. The family of OAM modes is mapped on an orbital Poincare sphere, and the modes position on the sphere is spanned by the three orbital parameters. Using the non-degenerate OPO we produce squeezing of these parameters, and as an illustration, we reconstruct the "cigar-shaped" uncertainty volume on the orbital Poincare sphere.