Emission of OAM entangled photon pairs in a nonlinear ring fiber utilizing spontaneous parametric down-conversion

TL;DR

This paper proposes a method to generate entangled photon pairs with orbital angular momentum in a nonlinear ring fiber using spontaneous parametric down-conversion, enabling control over their spectral properties.

Contribution

It introduces a novel approach for producing OAM-entangled photon pairs in a thermally induced nonlinear fiber with tunable spectral bandwidths.

Findings

Efficient generation of OAM-entangled photon pairs demonstrated.

Ability to produce both narrow- and broad-band down-converted fields.

Identification of optimal spatial and polarization modes for nonlinear interaction.

Abstract

We suggest the generation of photon pairs in a thermally induced nonlinear periodically-poled silica fiber by spontaneous parametric down-conversion. Photons are generated directly in eigenstates of optical angular momentum. Photons in a pair can be entangled in these states as well as in frequencies. We identify suitable spatial and polarization modes giving an efficient nonlinear interaction. By changing the pump field properties both narrow- and broad-band down-converted fields can be obtained.