Active engineering of four-wave mixing spectral entanglement in hollow-core fibers

TL;DR

This paper demonstrates both theoretically and experimentally how to control four-wave mixing in hollow-core fibers filled with inert gas to generate tunable entangled or separable photon pairs with high spectral precision.

Contribution

It introduces a method to manipulate the spectral entanglement of photon pairs using the dispersion properties of gas-filled hollow-core fibers, enabling dynamic control over photon pair characteristics.

Findings

Successful generation of spectrally entangled and separable bi-photons

Frequency tuning range of 17 THz achieved

Experimental control over joint spectral intensity profiles

Abstract

We demonstrate theoretically and experimentally a high level of control of the four-wave mixing process in an inert gas filled inhibited-coupling guiding hollow-core photonic crystal fiber in order to generate photon pairs. The specific multiple-branch dispersion profile in such fibers allows both entangled and separable bi-photon states to be produced. By controlling the choice of gas, its pressure and the fiber length, we experimentally generate various joint spectral intensity profiles in a stimulated regime that is transferable to the spontaneous regime. The generated profiles cover both spectrally separable and entangled bi-photons and feature frequency tuning over 17 THz, demonstrating the large dynamic control offered by such a photon pair source.