| Date | 29th, Jul 2020 |
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Quantum networks are going to replace conventional data networks – it’s just a matter of time when this is going to happen. However, until then a number of technical issues remain to be solve in order to ensure robustness of this novel technology.
Creation of strong security mechanisms is particularly widely-discussed issue related to quantum-based data transmission. The implementation of cryptographic protocols based on principles of quantum mechanics, or so-called quantum key distribution, is critically important to the security of quantum networks.
In a new research paper, a team of scientists present experimental demonstration of a modified Ekert quantum key distribution protocol using a quantum-dot entangled-photon source. The authors state that such type of protocol is already enough advanced to be suitable for real-world applications reaching beyond lab experiments.
Entanglement-based protocols offer additional layers of security and scale favorably with quantum repeaters, but the stringent requirements set on the photon source have made their use situational so far. Semiconductor-based quantum emitters are a promising solution in this scenario, ensuring on-demand generation of near-unity-fidelity entangled photons with record-low multi-photon emission, the latter feature countering some of the best eavesdropping attacks. Here we first employ a quantum dot to experimentally demonstrate a modified Ekert quantum key distribution protocol with two quantum channel approaches: both a 250 meter long single mode fiber and in free-space, connecting two buildings within the campus of Sapienza University in Rome. Our field study highlights that quantum-dot entangled-photon sources are ready to go beyond laboratory experiments, thus opening the way to real-life quantum communication.
Research paper link: https://arxiv.org/abs/2007.12727
