Polarization entangled photon-pair source based on a type-II PPLN waveguide emitting at a telecom wavelength

TL;DR

This paper demonstrates a fiber-coupled polarization entangled photon-pair source at telecom wavelength using a type-II PPLN waveguide, achieving near-perfect interference visibility suitable for quantum communication.

Contribution

The work introduces a high-performance, fiber-coupled entangled photon source based on a birefringent titanium in-diffused PPLN waveguide with record-high interference visibilities.

Findings

Near 100% two-photon interference visibility

Effective fiber coupling at 1310 nm

Potential for long-distance quantum communication

Abstract

We report the realization of a fiber coupled polarization entangled photon-pair source at 1310 nm based on a birefringent titanium in-diffused waveguide integrated on periodically poled lithium niobate. By taking advantage of a dedicated and high-performance setup, we characterized the quantum properties of the pairs by measuring two-photon interference in both Hong-Ou-Mandel and standard Bell inequality configurations. We obtained, for the two sets of measurements, interference net visibilities reaching nearly 100%, which represent important and competitive results compared to similar waveguide-based configurations already reported. These results prove the relevance of our approach as an enabling technology for long-distance quantum communication.