Interference between independent photonic integrated devices for quantum key distribution

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.

References in corpus (5)

• Secure Quantum Key Distribution
• Hacking commercial quantum cryptography systems by tailored bright illumination
• Breaking a quantum key distribution system through a timing side channel
• Interference of short optical pulses from independent gain-switched laser diodes for quantum secure communications
• Hong-Ou-Mandel interference between independent III-V on silicon waveguide integrated lasers

Cited by in corpus (1)

• Hong-Ou-Mandel interference between independent III-V on silicon waveguide integrated lasers