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arXiv · 1901.05706

Interference between independent photonic integrated devices for quantum key distribution

Henry Semenenko·Philip Sibson·Mark G. Thompson·Chris Erven
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Abstract

Advances in quantum computing are a rapidly growing threat towards modern cryptography. Quantum key distribution (QKD) provides long-term security without assuming the computational power of an adversary. However, inconsistencies between theory and experiment have raised questions in terms of real-world security, while large and power-hungry commercial systems have slowed wide-scale adoption. Measurement-device-independent QKD (MDI-QKD) provides a method of sharing secret keys that removes all possible detector side-channel attacks which drastically improves security claims. In this letter, we experimentally demonstrate a key step required to perform MDI-QKD with scalable integrated devices. We show Hong-Ou-Mandel interference between weak coherent states carved from two independent indium phosphide transmitters at $431$ MHz with a visibility of $46.5 \pm 0.8\%$. This work demonstrates the feasibility of using integrated devices to lower a major barrier towards adoption of QKD in metropolitan networks.

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Henry Semenenko, Philip Sibson, Mark G. Thompson, Chris Erven. 2019-01-17. Interference between independent photonic integrated devices for quantum key distribution. https://doi.org/10.1364/ol.44.000275

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