Loss of polarization entanglement in a fiber-optic system with polarization mode dispersion in one optical path

TL;DR

This paper investigates how polarization mode dispersion in a fiber-optic system degrades polarization entanglement, showing that entanglement diminishes with increased PMD and identifying optimal bandwidth conditions for maximum tolerance.

Contribution

It provides both theoretical and experimental analysis of entanglement loss due to PMD, revealing optimal pump bandwidth for enhanced entanglement preservation in fiber systems.

Findings

Entanglement decreases as PMD increases.

Maximum PMD tolerance occurs at specific pump bandwidths.

Experimental results confirm theoretical predictions.

Abstract

We characterize theoretically and experimentally the degradation of polarization entanglement in a fiber-optic entanglement distribution system where one of the optical fibers is exposed to the effects of polarization mode dispersion (PMD). We show gradual reduction of entanglement with increasing PMD and find that the highest PMD tolerance is achieved when the bandwidth of the pump used to generate the entangled photons in a $\chi^{(3)}$ process is approximately half the bandwidth of the quantum channels.