Integrated optical source of polarization entangled photons at 1310 nm

TL;DR

This paper presents a compact, reliable polarization entangled photon source at 1310 nm using a titanium-indiffused waveguide on lithium niobate, suitable for long-distance quantum communication.

Contribution

The authors developed a new integrated optical source of polarization entangled photons at telecom wavelength with high brightness and stability.

Findings

Achieved 85% two-photon coalescence visibility.

Generated photon pairs at 1310 nm with a bandwidth of 0.7 nm.

Source brightness of approximately 10^5 pairs per second per GHz per mW.

Abstract

We report the realization of a new polarization entangled photon-pair source based on a titanium-indiffused waveguide integrated on periodically poled lithium niobate pumped by a CW laser at $655 nm$. The paired photons are emitted at the telecom wavelength of $1310 nm$ within a bandwidth of $0.7 nm$. The quantum properties of the pairs are measured using a two-photon coalescence experiment showing a visibility of 85%. The evaluated source brightness, on the order of $10^5$ pairs $s^{-1} GHz^{-1} mW^{-1}$, associated with its compactness and reliability, demonstrates the source's high potential for long-distance quantum communication.