Single pairs of time-bin entangled photons

TL;DR

This paper presents a high-rate, secure source of single time-bin entangled photon pairs generated from a site-controlled quantum dot, suitable for long-distance quantum communication.

Contribution

It introduces a novel method to produce single time-bin entangled photon pairs from a quantum dot with maintained entanglement strength at high rates.

Findings

Each excitation pulse generates at most one entangled pair

High creation rates achieved without compromising entanglement quality

Suitable for secure long-distance quantum communication

Abstract

Time-bin entangled photons are ideal for long-distance quantum communication via optical fibers. Here we present a source where, even at high creation rates, each excitation pulse generates at most one time-bin entangled pair. This is important for the accuracy and security of quantum communication. Our site-controlled quantum dot generates single polarization-entangled photon pairs, which are then converted, without loss of entanglement strength, into single time-bin entangled photon pairs.